The White House clarified President Joe Biden’s comments after he said the U.S. would defend Taiwan if it was attacked by China, in what appeared to be a significant shift in U.S. foreign policy.

When asked by CNN anchor Anderson Cooper at a Thursday town hall event whether Biden would defend Taiwan if China attacked it, the president replied: “Yes, we have a commitment to do that.”

Aggressive Chinese rhetoric and military activity in recent months have raised tensions in Taiwan, which has for decades governed itself as an independent state and which China claims as part of its sovereign territory.

The comments appeared to be a departure from the policy of “strategic ambiguity” that the U.S. has long adopted towards Taiwan. The policy means that the U.S. has deliberately not indicated whether it would help Taiwan if it was invaded.

A White House spokesperson subsequently said the president’s comments had not signaled a shift in policy.

“The U.S. defense relationship with Taiwan is guided by the Taiwan Relations Act,” the spokesperson told reporters, according to The Guardian.

“We will uphold our commitment under the act, we will continue to support Taiwan’s self-defense, and we will continue to oppose any unilateral changes to the status quo.”

Under the Taiwan Relations Act, the U.S. provides the island with support, but they are not bound in a formal military alliance, the Financial Times reported.

China’s aggressive posturing toward Taiwan has increased in recent months.

An op-ed published earlier this month in the Global Times, a state-run Chinese tabloid, said Taiwan’s current status would “definitely come to an end” and said China will “teach Taiwan independence forces a hard lesson.”

A record number of warplanes also entered the island’s air defense zone for several days in a row earlier in October.

In a Friday statement issued through the Global Times, a spokesman for the Chinese Foreign Ministry said: “No one should underestimate the strong resolve, determination, and capability of the Chinese people to safeguard national sovereignty and territorial integrity.”

Reuters reported on Friday that White House officials were preparing for a virtual meeting between Biden and Chinese President Xi Jinping at an unspecified time.

This article was written by Thomas Colson and originally published on the Insider.