SINGAPORE—A tariff agreement with Vietnam emphasizes one of the White House’s top priorities in this frantic round of dealmaking over global trade: Slamming shut any back door routes for Chinese goods to enter the U.

Vietnam on Thursday hailed as a breakthrough a long-awaited trade deal with the United States and said its negotiators were coordinating with U.S. counterparts to formalise terms with Washington,

The Trump administration’s new trade deal with Vietnam aims to shut down any “backdoor” routes that allow Chinese goods to