Chinese President XI Jinping told U.S. Counterpart Donald Trump that bilateral relations were “Affected by some negative factors.”

Xi said in a phone call that Sino-U.S. Relations “Have achieved important results” since the two met at Trump’s Florida resort in April.

But xi was also quoted as saying, relations “have been affected by some negative factors”.

Days after trump approved a $1.3 billion U.S. Arms sales to Taiwan, XI said he hoped the U.S. President will “Properly Handle” Taiwan-related issues in accordance with the “one china” principle regarding the self-governed island.

The white house earlier said Trump and XI discussed efforts to denuclearise North Korea and improve U.S.-Chinese trade relations, but the U.S. Statement did not mention Taiwan.

Relations between the two nations had been warmer since Trump and XI met in April, but Washington has taken a series of actions that have infuriated Beijing in recent days.