Neither side has released documentation of the tariff terms, raising questions about whether they did, in fact, reach an agreement.

Vietnam’s negotiators had not, in fact, agreed to the 20% rate; they believed the tariff rate would be around 11%, according to the four people.

Some on the U.S. side were surprised, too, including outside groups who’d been tracking the talks, according to one Washington-based lobbyist who works with Vietnam and other Asian governments.

“Trump sandbagged everybody,” said the lobbyist. They described the Vietnamese government’s reaction as “surprise, as well as disappointment and anger.”