Beijing has asked the Houthis directly to promise safe passage for its tankers, according to the sources, who included a senior Iranian official. China’s transport ministry, the Houthis’ media office and Iran’s Foreign Ministry did not immediately respond to requests for comment. Some tankers trying to enter the Red Sea through the Bab el-Mandeb have changed course because of safety worries, two separate Chinese trade sources said. The Houthis last week had carried out missile and drone strikes on two Saudi oil tankers. The Houthis have maintained good relations with China and there has been ​close coordination in the past between ​them, especially on oil shipments to China from Saudi Arabia, two sources close to the Houthis told Reuters.