US President Donald Trump looked to patch up relations with China by promising to honor the "One China" agreement between the world's two biggest economies on his first phone call as president with Chinese President Xi Jinping.

A press release from the White House said that during an "extremely cordial" and "lengthy" conversation on Thursday evening, the "two leaders discussed numerous topics and that Trump agreed, at the request of President Xi, to honor our 'one China' policy."

The release also said the two leaders extended invitations to meet in their respective countries and representatives of each country "will engage in discussions and negotiations on various issues of mutual interest."

Trump rattled the US's relationship with China after his inauguration by breaking with decades of US policy and taking a call from Taiwanese President Tsai Ing-Wen in December.

The "One China" policy, to which the US and China agreed in 1972, holds that China and Taiwan belong to a single country. Many on the island of Taiwan, officially known as the Republic of China, see themselves as the legitimate government-in-exile of all of China after the Communist Party took control of the mainland.

For that reason, recognition of Taiwan internationally poses an existential threat to China. China has warned Trump that the "One China" policy between the US and China was nonnegotiable.

The White House said Wednesday that Trump had provided Xi with a letter to correspond with Xi's written well wishes on Trump's inauguration. In the letter, the White House said, Trump told Xi he "looks forward to working with President Xi to develop a constructive relationship that benefits both the United States and China."