Northern Limit Line

Incidents have occured in waters south of the Northern Limit Line, shown in red separating North and South Korea

The Northern Limit Line or North Limit Line (NLL) is a disputed inter-Korea maritime demarcation line in the Yellow (West) Sea between the Democratic People's Republic of Korea (DPRK) on the north, and the Republic of Korea (ROK) on the south. This line of military control acts as the de facto maritime boundary between North and South Korea.

Description

The line runs between the mainland portion of Gyeonggi-do province that had been part of Hwanghae before 1945, and the adjacent offshore islands, including Yeonpyeong and Baengnyeongdo. Because of the conditions of the armistice, the mainland portion reverted to North Korean control, while the islands remained a part of South Korea despite their close proximity. The line continues to extend into the sea from the Military Demarcation Line (MDL). In 1977 North Korea attempted to establish a 50 mile military boundary zone around the islands claimed by South Korea along the NLL; however, the claims were rebuffed. Since 1999, North Korea has claimed a more southerly "West Sea Military Demarcation Line".

Origins

A US Government map showing where a North Korean 12 nautical mile territorial waters limit would be, when disregarding the north west UN Command islands, compared to the Northern Limit Line.

The 1953 Armistice Agreement which was signed by both North Korea and the United Nations Command, ended the Korean War and specified that the five islands including Yeonpyeong Island, Baengnyeong Island would remain under United Nations Command and South Korean control. However, they did not agree on a maritime demarcation line, primarily because the United Nations Command wanted to base it on three nautical miles of territorial waters, while North Korea wanted to use twelve nautical miles.

After the United Nations Command and North Korea failed to reach an agreement, the line was set by the United Nations military forces on August 30, 1953. As a result, while the NLL was not part of the armistice signed in July of that year, the United Nations Command drew up the NLL the following month as a practical operational control measure based on straight line segments between 12 approximate channel midpoints, extended in an arc to prevent egress between both sides. On its western end the line extends out along the 38th parallel to the median line between Korea and China. The line was originally drawn to prevent southern incursions into the north. However, its role has since been transformed to prevent North Korean ships heading south.

Whilst the NLL was drawn up at a time when a three nautical mile territorial waters limit was the norm, by the 1970s a twelve nautical mile limit had became internationally accepted, and the enforcement of the NLL prevented North Korea, in areas, from accessing significant territorial waters (arguably actual or prospective). In 1973, North Korea began disputing the NLL. Later, after the 1982 United Nations Convention on the Law of the Sea, the NLL also hindered North Korea's ability to establish an Exclusive Economic Zone to control fishing in the area.

It is unclear when North Korea was informed of the existence of the NLL. Many sources suggest this was done promptly, but in 1973 Deputy Secretary of State Kenneth Rush stated, in a now declassified, "Joint State-Defense Message" to the U.S. Embassy in Seoul that "We are aware of no evidence that NLL has ever been officially presented to North Korea." However, South Korea argues that until the 1970s North Korea tacitly recognized the line as a sea demarcation line. The North records the NLL as a sea demarcation line on Chosun Central Yearbook published by North Korean authorities.

Status

The border is not officially recognized by North Korea. The North Korean and South Korean navies regularly patrol the area around the NLL. As North Korea does not recognise the line, its fishing boats work close to or over the limit line, escorted by North Korean naval boats.

United Nations Command position

The United Nations Command (UNC) emphasized its position on the border issue on 23 August 1999. The United Nations Command side stated that the NLL issue was nonnegotiable, because the demarcation line had been recognized as the de facto maritime border for long years by both Koreas.

"The NLL has served as an effective means of preventing military tension between North and South Korean military forces for 46 years. It serves as a practical demarcation line, which has contributed to the separation of forces."

- 1999. 6. 11, United Nations Command

The United Nations Command insisted that the NLL must be maintained until a new maritime MDL could be established through the Joint Military Commission on the armistice agreement.

However in a 1973 U.S. diplomatic cable, now declassified, noted that United Nations Command protested North Korean intrusions within the three nautical-mile waters of UNC controlled islands as armistice agreement violations, but did not protest NLL intrusions as the NLL was not mentioned in the armistice agreement. South Korea wished to describe all NLL penetrations as "military provocations", but the U.S. saw that as a major problem for the U.S. position on the armistice agreement.

North Korea's position

When the 1953 Armistice was concluded between the U.N. and North Korea, agreement over a maritime extension of the demilitarized zone was not achieved. In 1955, DPRK proclaimed territorial waters extending 12 nm. from the coastline. Other than this, North Korea did not explicitly dispute the NLL nor did the DPRK actively violate the NLL until 1973, when it started to openly dispute the border by sending large groups of patrol ships over the NLL on about 43 occasions. North Korea's official state news agency KCNA has described the line as the "final line for stopping the defectors to the north" drawn to meet "Washington's self-justified interests."

With the collapse of the Soviet Union in 1991, North Korea wanted to establish a special economic zone and international port at Haeju, their southern deepwater port, to develop alternative trade opportunities. However with the NLL enforced, access to Haeju required shipping to travel along North Korean coast for 65 nautical miles, often within 3 nautical miles of the shore. This prevents the development of Haeju as a large international port.

On December 21, 2009, North Korea established a "peacetime firing zone" south of the NLL in waters disputed with South Korea.

South Korea's position

The South Korean position from the 1970s has been:

• The NLL is an indispensable measure to administer the Armistice Agreement;
• The NLL is in the approximate mid-position between the islands and the North Korean mainland;
• North Korea acquiesced to the NLL until 1973, so implicitly recognized the NLL.

In 2002 the Ministry of National Defense published a paper reasserting the legitimacy of the NLL, and arguing that North Korea's claims regarding NLL were groundless. The paper concluded that:

• The NLL has been the practical sea demarcation line for the past 49 years and was confirmed and validated by the 1992 South-North Basic Agreement;
• Until a new sea nonaggression demarcation line is established, the NLL will be resolutely maintained like the ground Military Demarcation Line, and decisive responses will be made to all North Korean intrusions;
• Any new sea nonaggression demarcation must be established through South-North discussions, and the NLL is not the subject of negotiation between the US or UNC and the North;
• North Korea's claims violate the Armistice Agreement and are not compatible with the spirit and provisions of international law.

On October 4, 2007, South Korean President Roh Moo-hyun and North Korean leader Kim Jong-il addressed the issue of NLL disputes in a joint statement:

"The South and the North have agreed to create a ‘special peace and cooperation zone in the West Sea’ encompassing Haeju and vicinity in a bid to proactively push ahead with the creation of a joint fishing zone and maritime peace zone, establishment of a special economic zone, utilization of Haeju harbor, passage of civilian vessels via direct routes in Haeju and the joint use of the Han River estuary."

However the following South Korean President Lee Myung-bak rejected this approach, describing the NLL as a "critical border that contributes to keeping peace on our land."

United States position

The United States government position, seperate from the United Nations Command, is not clearly expressed. When asked about the NLL, United States government representatives usually refer questioners to the United Nations Command in South Korea.

In February 1975, Secretary of State Henry Kissinger wrote in a confidential cable, now declassified, that the "Northern Patrol Limit Line does not have international legal status ... Insofar as it purports unilaterally to divide international waters, it is clearly contrary to international law and USG Law of the Sea position." Earlier in 1973 a "Joint State-Defense Message" to the U.S. Embassy in Seoul stated that South Korea "is wrong in assuming we will join in attempts to impose NLL", and the U.S. Ambassador told the South Korean government that the 12-mile North Korean territorial sea claim created a zone of uncertain status with respect to the NLL.

In November 2010, following the North Korean Shelling of Yeonpyeong, President Barack Obama said the U.S. stood "shoulder to shoulder" with South Korea and condemned the attack, but did not specifically address the NLL.

Border clashes

The disputed maritime border between North and South Korea in the West Sea:
  A: United Nations-created Northern Limit Line, 1953
  B: North Korea-declared "Inter-Korean MDL in the Yellow Sea", 1999 The locations of specific islands are reflected in the configuration of each  maritime boundary, including
    1–Yeonpyeong Island
    2–Baengnyeong Island
    3–Daecheong Island

---

Other map features
Other map features: 4-Jung-gu (Incheon Intl. Airport), 5-Seoul, 6-Incheon, 7-Haeju, 8-Kaesong, 9-Ganghwa County, 10-Bukdo Myeon, 11-Deokjeokdo, 12-Jawol Myeon, 13-Yeongheung Myeon

Main article: Korean maritime border incidents

Disputes between North and South Korean naval vessels, dubbed "crab wars", often occur in this area. Occasionally violence flares up along the line and deadly skirmishes occur.

Major incidents include:

• First Battle of Yeonpyeong (1999) - four North Korean patrol boats and a group of fishing boats crossed the border and initiated a gun battle that left one North Korean vessel sunk, five patrol boats damaged, 30 sailors killed, and 70 wounded.
• Second Battle of Yeonpyeong (2002) - two North Korean patrol boats crossed the NLL near Yeonpyeong island and started firing; after becoming outnumbered and suffering damage, the vessels retreated.
• Battle of Daecheong (2009) - A North Korean gun boat crossed the NLL and entered waters near Daecheong Island, became heavily damaged, and turned back.
• ROKS Cheonan sinking (2010) - The Cheonan, a South Korean corvette, was sunk by an explosion, killing 46 sailors; the resulting South-Korea-led international investigation blamed North Korea, which denied involvement.
• Shelling of Yeonpyeong (2010) - North Korean forces fired around 170 artillery shells at Yeonpyeong, killing four South Koreans, injuring 19, and causing widespread damage to the island's civilian fishing village.

Other minor incidents include:

• On 1 November 2004 three North Korean vessels crossed the NLL. They were challenged by South Korean patrol boats, but did not respond. The ROK vessels opened fire and the DPRK boats withdrew without returning fire. No casualties were reported.

• On November 10, 2009, naval vessels from the two Koreas exchanged fire in the area of the NLL, reportedly causing serious damage to a North Korean patrol ship and one death.

• On January 27, 2010, North Korea fired artillery shots into the water near the NLL and South Korean vessels returned fire. The incident took place near the South Korean-controlled Baengnyeong Island. Three days later, North Korea continued to fire artillery shots towards the area.

Totals

Altogether, the disputes have resulted in:

• 53 North Korean military personnel killed
• 54 South Korean military personnel killed
• 95 North Korean military personnel wounded
• 99 South Korean military personnel wounded
• 2 South Korean civilians killed
• 3 South Korean civilians wounded

Materiel losses and damage include:

• 1 North Korean torpedo boat sunk
• 1 North Korean gunboat damaged
• 6 North Korean patrol boats damaged
• 1 South Korean corvette sunk
• 1 South Korean patrol boat sunk
• 1 South Korean corvette damaged
• 2 South Korean patrol boats damaged

See also

• Korean Demilitarized Zone
• Military Demarcation Line
• Armistice Agreement of 1953 - Wikisource has the full text of the armistice signed in 1953.