New trade talks between the two governments are tentatively scheduled between Steven Mnuchin, the Treasury secretary, and Liu He, a Chinese vice premier, later this month in Washington. Stephen A. Schwarzman, Blackstone’s chief, has been playing a critical role in organizing them, say people familiar with the talks, who asked for anonymity because the process is sensitive.

But the Chinese have indicated that they will pull out of the talks if Mr. Trump follows through on his threat to impose tariffs on another $200 billion in Chinese goods, according to a person familiar with the matter. Mr. Trump has told advisers that he wants to move ahead with the new round of tariffs and an announcement could come as early as this week, another person familiar with the discussions said.

That continues a frustrating trend for America’s financial titans: Even as they win tax cuts and regulatory rollbacks from the Trump administration and the Republican-controlled Congress, they appear to be able to do little to stop the trade war.

“What’s really surprising is that the connections that used to work, the formula that used to work, just don’t work at this point,” said Marshall W. Meyer, an emeritus professor of management at the Wharton School of Business.

Wall Street has long gambled that helping China would pay off. China has been slow to open its vast but tightly controlled financial markets, and Wall Street banks hope to get more business advising Chinese companies on acquisitions in the United States, lending money and selling financial services. Pressure from the Trump administration is now bearing fruit as China has begun to open its financial markets to foreign banks.