Before leaving for a high-level summit with Xi Jinping in Beijing, Donald Trump said that he was open to discussing US arms sales to Taiwan with the Chinese leader. The US president also acknowledged that Taiwan would be a major topic in talks with Mr Xi . China regards the self-governed island of Taiwan as a breakaway territory and opposes any involvement by foreign powers in its domestic affairs or its relations with Beijing. The US follows a “One China policy”, meaning it recognises Beijing’s position without taking a stance on whether Taiwan is sovereign. At the same time the US is Taiwan’s strongest international supporter and is legally required to help the island defend itself. Asked if the US should keep selling weapons to Taiwan, a key irritant in Washington’s ties with Beijing , Mr Trump wouldn’t answer directly. “I am going to have that discussion with President Xi,” he said. “President Xi would like us not to, and I’ll have that discussion.…