Wen will also visit Qatar and the United Arab Emirates, fellow members of the Organization of Petroleum Exporting Countries, during the Persian Gulf tour ending Jan. 19. "China seems quite reluctant to get on the wrong side of Iran given the tensions existing in the region and Iran's importance for its oil," Paul Sullivan, a political scientist specializing in Middle East security at Georgetown University in Washington, said in a Jan. 11 e-mail. Wen will become the most senior Chinese leader to travel to Saudi Arabia since President Hu Jintao in 2009. His visit will begin as Saudi Arabian Oil Co. and China Petroleum & Chemical Corp. (600028) sign an agreement for a proposed refinery on the Red Sea coast. Sinopec's planned 37.5 percent stake in the Yanbu plant would make it China's first investment in a Saudi oil facility. The European Union and the U.S. are weighing more stringent sanctions against Iran over its nuclear program.