Tariff and trade wars "undermine the legitimate rights and interests of all countries, hurt the multilateral trading system, and impact the world economic order", he told Azerbaijani President Ilham Aliyev, state news agency Xinhua reported.

Beijing and Washington have been embroiled in a blistering trade war since US President Donald Trump this month slapped a 145 percent blanket tax on Chinese imports.

China responded with a 125 percent duty on goods from the United States.

Beijing's commerce ministry this week warned other nations to be wary in seeking a deal with Washington.

"China firmly opposes any party reaching a deal at the expense of China's interests," a ministry spokesperson said Monday in a statement.

"Appeasement will not bring peace, and compromise will not be respected," the statement said.

On Wednesday, Xi said that "despite a constantly changing international situation", China and Azerbaijan had maintained close ties.

A day earlier, in phone calls with his British and Austrian counterparts, Chinese foreign minister Wang Yi urged Britain and the European Union to help in defending multilateral trade.