U.S. President Donald Trump asked Japanese Prime Minister Sanae Takiachi to avoid further escalation of a dispute with China during talks this week, sources with knowledge of the matter said, as he aims to keep a fragile trade war truce with Beijing.

Takaichi touched off the biggest diplomatic dispute with Beijing in years with comments in parliament this month that a hypothetical Chinese attack on Taiwan could trigger Japanese military action, inciting fury in Beijing.

In Tuesday's telephone call with Takaichi, Trump said he did not want to see any further escalation, said the two Japanese government sources, who sought anonymity as the matter is a sensitive one.

Trump made no specific demands of Takaichi, however, one of the sources said, suggesting that he did not echo Beijing's call for a retraction of the comments. Japan has not offered one, saying instead that the remarks reflected longstanding policy.