U.S. Trade Representative Jamieson Greer appeared to break with President Donald Trump on Sunday over the issue of arms sales to Taiwan, insisting there is “no change in American policy” just days after his boss openly stated that he was using arms sales to the island as a bargaining chip in negotiations with China.

Doing so would violate decades-old foreign policy assurances for the island, something that Trump acknowledged during remarks to reporters last week. But Greer on Sunday seemed to contradict the president during an interview on ABC’s “This Week.”

“The most important thing that needs to happen is we need to have no change in the status quo in the Taiwan Straits, and the president was really clear about this,” Greer said.

The U.S. approved a record-breaking $11.1 billion arms sale to Taiwan in December, but the deal is effectively stuck in limbo as manufacturing and contract procurement stall the final delivery of weapons. The sale includes advanced rocket systems, anti-tank missiles and munition drones, among other artillery.

A separate $14 billion package is set to expand on the equipment from the $11.1 billion deal and bolster Taiwan’s air defense capabilities, but that proposed sale is awaiting approval from the president.

Trump teased using both packages as leverage in negotiations with Chinese President Xi Jinping ahead of last week’s U.S.-China summit.

U.S. policy regarding weapons shipments to the self-governing territory — which China claims to have sovereignty over — dates to 1979, when the U.S. recognized the People’s Republic of China as the sole, legitimate government of the country. That year, the Taiwan Relations Act became the cornerstone of U.S.-Taiwan policy. The act mandates that the U.S. provide Taiwan with arms of a “defensive character.”

Four years later, President Ronald Reagan established the Six Assurances to clarify earlier commitments made to the Taiwanese government and further insulate U.S.-Taiwan relations from Chinese influence. One key provision of the six assurances states that the U.S. would not consult with Beijing before making decisions about arms sales to Taiwan.

But Trump said last week that he deferred to China when asked if he plans to approve the stalled $14 billion arms package to Taiwan.

“I’m holding that in abeyance and it depends on China,” Trump said in an interview with Fox News after the summit. “It’s a very good negotiating chip for us, frankly. It’s a lot of weapons.”

“What am I going to do, say I don’t want to talk to you about it because I have an agreement that was signed in 1982?” Trump added on Friday, telling reporters he discussed the arms sales with Xi “in great detail, actually.”

The president told reporters Friday that he needed to speak to the person “that’s running Taiwan” before deciding about the arms package, and said he “made no commitment” during the summit. There have not been many instances of direct diplomatic communication between U.S. presidents and Taiwanese leaders since 1979, but in 2016 when Trump was the president-elect, he spoke directly with Taiwan’s president at the time on a call.

Ambassador Alexander Yui, Taiwan’s representative to the U.S., confirmed Sunday that a call between Trump and Taiwan President Lai Ching-te has not been scheduled, but noted that “the communication between Taiwan and U.S. is constant” in an interview on CBS’ “Face the Nation.”

Ching-te said arms sales to the island were “the most important deterrent” for regional conflict and called on the U.S. to support the weapons deal in a post on social media.

“The United States’ continued arms sales to Taiwan and deepening of Taiwan-U.S. security cooperation are not only necessary but also key elements in maintaining regional peace and stability,” Ching-te said in the statement.