China's leader Xi Jinping called Taiwan "the most important issue" in China-US relations during a phone call with US President Donald Trump on Wednesday, BBC reported. 

Xi had told Trump to be "prudent" when supplying weapons to the island, state media reported, adding that he "attaches great importance" to ties with Washington and hoped both sides will find ways to resolve their differences.

Trump cast the call as "excellent" and "long and thorough".