WASHINGTON, DC, United States (AP) — The Trump Aadministration moved yesterday to block Chinese airlines from flying to the US in an escalation of trade and travel tensions between the two countries.

The Transportation Department said it would suspend passenger flights of four Chinese airlines to and from the United States, starting June 16.

The decision was in response to China’s failure to let United Airlines and Delta Air Lines resume flights to China this month. The airlines suspended those flights earlier this year in response to the coronavirus pandemic that started in China’s Wuhan province.

The Transportation Department said that China was violating an agreement between the two countries covering flights by each other’s airlines.

“The Department will continue to engage our Chinese counterparts so both US and Chinese carriers can fully exercise their bilateral rights,” the agency said in a statement. “In the meantime, we will allow Chinese carriers to operate the same number of scheduled passenger flights as the Chinese Government allows ours.”

The department said President Donald Trump could put the order into effect before June 16. The Administration had hinted at the move last month, when it protested to Chinese authorities that Beijing was preventing US airlines from competing fairly against Chinese carriers.

The four airlines affected by the order are Air China, China Eastern Airlines, China Southern Airlines and Xiamen Airlines.

Before the pandemic, there were about 325 passenger flights a week between the United States and China, including ones operated by United, Delta and American Airlines. While US carriers stopped their flights, Chinese airlines continued to fly about 20 times a week between the two countries by mid-February and increased that to 34 flights a week by mid-March, according to the Transportation Department.

United and Delta announced last month that they hoped to resume flights to China in June, as air travel has recovered slightly since mid-April. American Airlines’ schedule shows flights resuming in October; it has not announced any plans to restart service sooner.