Commerce Secretary Wilbur Ross softened expectations of any major breakthrough from U.S. and China talks over trade issues this week.

Ross is part of a U.S. delegation led by Treasury Secretary Steven Mnuchin that’s traveling to Beijing to meet with Chinese officials of equal seniority, he said in an interview on CNBC on Tuesday. The meetings will start Thursday and the U.S. officials plan to head home by the weekend, though the trip could be cut short “if it’s not satisfactory,” said Ross.

“You never know where you are until you actually get into the conference room” and an outcome can’t be prejudged, said Ross. “I wouldn’t be going all the way over there if I didn’t think there was some hope.”

The White House is threatening to slap massive tariffs on Chinese imports in a bid to narrow its trade deficit with the Asian nation, which ballooned to $337 billion last year. Beijing’s pledge to retaliate with barriers of its own against American goods has raised the specter of a trade war that the International Monetary Fund cautions could undermine global growth.

Mnuchin said in an interview on Monday that he was cautiously optimistic about the meetings in China. Other top trade and economic advisers traveling with Mnuchin include the White House’s Larry Kudlow and Peter Navarro and U.S. Trade Representative Robert Lighthizer.

The “Delegation heading to China to begin talks on the Massive Trade Deficit that has been created with our Country,” President Donald Trump said in a Twitter post on Tuesday. “Very much like North Korea, this should have been fixed years ago, not now. Same with other countries and NAFTA…but it will all get done. Great Potential for USA!”