In 1958, Zhou Enlai and Imam Muhammad Al-Badr of Yemen issued a joint communique and signed a treaty of friendship, including agreements on commercial, technical and cultural cooperation. According to the treaty, China granted Yemen a credit without interest of 70 million Swiss francs to be used for the payment of articles to be supplied by China to the people of Yemen. In addition to trade relations, conditions, and regulations, the full text of the treaty included exports from Yemen to China of raw coffee, cotton, cotton seed oil, oil bearing seeds, raw hides, tobacco, walnuts, apricot kernels, beans, salted fish, minerals, salt for industrial use, and silver products. Beijing also extended a $16.3 million, interest-free loan repayable in Swiss francs, sterling, or Yemen commodities, with repayment after the completion of individual projects. Under this credit about 800 Chinese engineers and laborers were engaged in building a road from Hodeida to Sana'a.
On June 9, 1964, China and Yemen signed a treaty of friendship, an agreement on economic and technical cooperation, and another on cultural cooperation. Eight Chinese experts arrived in Yemen by August 17, and another 28 by September 9, to help Yemen build a textile factory under the Sino-Yemeni Economic Technical Cooperation Agreement. In June 1964 President Abdallah al-Sallal made a similar visit to China and signed a treaty of friendship and two agreements-one on economic and technical cooperation, the other on cultural cooperation. The Beijing Government extended a $500,000 interest-free loan to the Yemeni Revolutionary Government and sent groups of technicians and engineers to help in the construction of roads and various plants.