U.S. Treasury Secretary Steven Mnuchin said on Monday the U.S. expects progress this week in trade talks with Chinese Vice Premier Liu He, but the two sides will be tackling “complicated issues” including how to enforce any deal, Reuters reported.

The talks, scheduled for Wednesday and Thursday in Washington D.C., will include a meeting between Liu and U.S. President Donald Trump and take place amid worsening tensions between the world’s two largest economies.

“We want to make sure that when we get a deal, that deal will be enforced,” Mnuchin was quoted as saying. “The details of how we do that are very complicated. That needs to be negotiated. But IP (intellectual property) protection, no more forced joint ventures, and enforcement are three of the most important issues on the agenda.”

Mnuchin reportedly said there had been “significant movement” in the talks so far, and there will be around 30 days for further negotiations after the meetings in Washington on Wednesday and Thursday to reach an agreement before a March 2 deadline for increasing U.S. tariffs on Chinese goods.

Reuters reported that mounting concerns for both countries, including China’s slowing economy and Trump’s need for a political win, could prod both sides toward a “partial, interim deal,” according to Eswar Prasad, a Cornell University trade professor and former head of the International Monetary Fund’s China department.

“There remains a vast distance separating the negotiating positions of the two sides, making a comprehensive and durable deal unlikely,” Prasad was quoted as saying.