Top trade officials from the U.S. and China were meeting in London on Monday, the second such meeting in the past month and one aiming to quell rising tensions between the two superpowers over tariffs and other trade policies.

The meeting kicked off just days after President Donald Trump and Chinese President Xi Jinping engaged in an extended phone conversation, after which Trump offered an upbeat download on the conversation.

“I just concluded a very good phone call with President Xi, of China, discussing some of the intricacies of our recently made, and agreed to, Trade Deal,” Trump said on Truth Social last Friday. “The call lasted approximately one and a half hours, and resulted in a very positive conclusion for both Countries. There should no longer be any questions respecting the complexity of Rare Earth products. Our respective teams will be meeting shortly at a location to be determined.”

U.S. Treasury Secretary Scott Bessent, Secretary of Commerce Howard Lutnick and U.S. Trade Representative, Ambassador Jamieson Greer are leading the U.S. delegation and early reports on the talks were optimistic.

National Economic Council Director Kevin Hassett on Monday told CNBC’s “Squawk Box” that the U.S. was seeking confirmation China would restore the flows of critical minerals.

“The purpose of the meeting today is to make sure that they’re serious, but to literally get handshakes … and get this thing behind us,” Hassett said.

He added that he expected it “to be a short meeting with a big, strong handshake.”

Will a new trade deal be reached?

While White House officials were signaling expectations for a positive outcome from the latest round of talks, some trade experts predicted the road to a new U.S.-China agreement could be a long one.

Zhiwei Zhang, president and chief economist of Pinpoint Asset Management, told CNBC that it could take months for trade tensions to be resolved.

“I don’t really have very high expectations for these trade talks … I doubt they will reach an agreement very soon,” he told CNBC on Monday.

“There could be some resolution on specific issues, like a rare earths, for instance, China already announced that they will give some permits to foreign firms applying for imports. Now, those kind of a temporary solution, we might see some of that come out. But I doubt we will have a complete solution coming from this dialogue in the U.K.,” Zhang added.

What led to new round of discussions

In spite of a temporary U.S.-China trade agreement coming out of talks held on May 12 in Geneva, Switzerland, tensions arose earlier this month after Trump accused China of breaching terms of the deal.

“The bad news is that China, perhaps not surprisingly to some, HAS TOTALLY VIOLATED ITS AGREEMENT WITH US. So much for being Mr. NICE GUY!” Trump wrote on Truth Social.

Last week, ahead of the call between Trump and Xi, China hit back on Trump’s claims the Asian country was in breach of a new trade agreement, countering that the U.S. itself was undermining the deal with new sanctions.

A statement from China’s Ministry of Commerce released last Monday said Trump administration actions “seriously undermine the existing consensus reached at the Geneva economic and trade talks, and seriously damage China’s legitimate rights and interests.”

Chinese officials also pointed to recent signaling from the U.S. about potential new regulations for advanced microchips and the revocation of U.S. visas for Chinese students, per CBS News, as evidence that the U.S. was acting in bad faith following the trade deal.

Trump’s complaint stemmed from his concerns over China’s export rules on rare earth minerals.

China controls 90% of the world’s rare earth elements production capacity and, according to the U.S. Department of Energy, the minerals play a critical role in U.S. national security, energy independence and economic growth. Many advanced technologies have components made from rare earth materials such as magnets, batteries, phosphors and catalysts.