Chinese policymakers on Monday sought to assuage concerns the broad U.S. tariffs could derail efforts to shore up a fragile economic recovery, even as analysts warn the hefty levies raise the risk of a sharp downturn in growth.

The Treasury secretary said that the President Trump and Xi Jinping of China have a good relationship but that he was not aware of a call, which Mr. Trump had alluded to last week.

China’s leader Xi Jinping has released a letter denouncing tariff and trade wars and urging the multilateral trading system, stable global industrial and supply chains, and open and