WASHINGTON (Reuters), -The U.S. president Joe Biden claimed Tuesday that he spoke to Chinese President Xi Jinping over Taiwan. The two agreed to abide to the Taiwan agreement as tensions are high between Taipei, Beijing.

“I spoke with Xi regarding Taiwan. “We agree…we’ll adhere to the Taiwan agreement,” said he. He said, “We have made it very clear that we don’t believe he should do anything but to abide by the agreement.”

Biden was referring to Washington’s decades-old “one China policy”, under which Washington recognizes Beijing more than Taipei. And the Taiwan Relations Act which clearly states that U.S. diplomatic ties to Beijing are based upon the belief that Taiwan’s future is determined peacefully.

These comments were made by the White House to reporters after Biden returned from Michigan with a spending plan. They are being made amid tensions in Taiwan-China relations.

China considers Taiwan its territory. If necessary, force should be used to retake it. Taiwan declares it is an independent nation and that it will fight for democracy and freedoms. China has been blamed for these tensions.

Taiwan reports 148 Chinese Air Force planes operating in its southern and southwest air defense zones. The reporting period spanned four days that began on Friday. It was also the day China observed a significant patriotic holiday called National Day.

China was urged by the United States to cease its military activity near Taiwan on Sunday

Ned Price, spokesperson for the State Department, stated that “The United States is extremely concerned about the People’s Republic of China’s provocational military activity near Taiwan”, in a Sunday statement.

Biden may also have been referring to a 90-minute conversation he had with Xi Sept. 9th, their first talk in seven months. In which they discussed how to make sure that the competition among the two world’s largest economies doesn’t veer into conflicts.