The top White House economic adviser Friday warned China not to underestimate the determination of President Donald Trump.

“Their economy’s weak, their currency is weak, people are leaving the country. Don’t underestimate President Trump’s determination to follow through,” Larry Kudlow said in an interview with Bloomberg TV.

Trade tensions between the U.S. and China have been rising this week. The Trump administration announced that it was considering raising the tariff it plans to apply to $200 billion of Chinese goods from 10 percent to 25 percent. China on Friday said it has prepared a list of an additional $60 billion of U.S. goods it would hit with tariffs if the U.S. moves ahead with its plan.

China’s currency has been dropping in value, which some have speculated could be an intentional manipulation to reduce the impact of U.S. tariffs. Kudlow, however, proposed another possibility: investors fleeing China.

“Some of the currency fall, I think, is just money leaving China because it’s a lousy investment, and if that continues that will really damage the Chinese economy,” Kudlow said. “If money leaves China, and the currency could be a leading indicator, they’re going to be in a heap of trouble.”