New Delhi, May 27 -- Uncertainty around tariff levels and trade policy broadly is high headed into the summer. But U.S. Trade Representative Chief Jamieson Greer offered some guidance Tuesday, raising the possibility that the 10% temporary tariffs set to expire in July could be reimposed and signaling some tariffs could be lowered on Chinese trade and elsewhere.

Greer, speaking at an event hosted by the Council on Foreign Relations, said the U.S. would have a tariff, even with neighbors like Mexico and Canada, as long as trade isn't balanced. However, he indicated several areas where those tariffs may not be as high as they were last year.

The average effective tariff rate stands at about 11.8% as of April, according to the Yale Budget ...