Chinese President Xi Jinping said Saturday he hopes to open a "new chapter" in relations with Iran after the lifting of international sanctions under a historic nuclear deal, as he paid the first visit by a Chinese leader to the Islamic Republic in 14 years. "In cooperation with the Iranian side and by benefiting from the current favorable conditions, China is ready to upgrade the level of bilateral relations and cooperation so that a new chapter will start in bilateral relations," Xi said after meeting with Iranian President Hassan Rouhani, according to Iranian state TV. Trade between the two countries stood at some $52 billion in 2014, but that figure dropped last year due to plunging oil prices. China is Iran's biggest trade partner, and continued purchasing oil from Iran after nuclear-related sanctions were tightened in 2012, despite U.S. pressure. "China has always stood by the side of the Iranian nation during hard days," Rouhani said, in comments posted on his official website.

Iran's Supreme Leader Ayatollah Ali Khamenei, who has the final say on all state matters, told Jinping later Saturday that Iran will continue its policy of bolstering ties with the "East." He praised China's "independent" stance in global issues, saying it helps deepen strategic ties with Tehran. "Westerners have never obtained the trust of the Iranian nation," he said. "The government and nation of Iran have always sought expanding relations with independent and trustful countries like China." Khamenei said Iran won't forget China's support at the time of sanctions. "The Islamic Republic will never forget China's cooperation during the sanctions era," state TV quoted Khamenei as saying.

Officials from the two countries signed 17 documents and letters of intent to broaden bilateral cooperation in industry, transportation, railways, ports, new technology, tourism, the environment and energy. China is one of six world powers along with the U.S., Germany, France, Britain and Russia that reached a landmark agreement with Iran last summer to lift international sanctions in exchange for Tehran curbing its nuclear program. The deal was implemented a week ago after the U.N. nuclear watchdog certified that Iran had fulfilled all its commitments.

Meanwhile, Secretary of State John Kerry said Sunday that the U.S. friendship with Saudi Arabia is stronger than ever and that the two will work together to try to end wars in Syria and Yemen. "We have as solid a relationship, as clear an alliance and as strong a friendship with the kingdom of Saudi Arabia as we have ever had, and nothing has changed because we worked to eliminate a nuclear weapon with a country in the region," he said, referring to the Iran nuclear deal. Kerry delivered the remarks to U.S. Embassy employees a day after meeting with Saudi and other Gulf officials on a visit aimed at reassuring U.S. allies who are skeptical about the agreement. Saudi Arabia and other Gulf countries have long viewed Iran as a regional menace, and Riyadh and Tehran back opposite sides in the wars in Syria and Yemen.