WASHINGTON (AP) — The nominee to become the next U.S. ambassador to Vietnam says it may be time for Washington to consider lifting a ban on the sale and transfer of lethal weapons to the former American enemy.

Ted Osius told his Senate confirmation hearing Tuesday that the U.S. has made clear to Vietnam the ban cannot be lifted without significant progress on human rights.

But he said there has been progress in three or four of the nine areas where the U.S. is looking for improvements.

Osius said that “may mean it’s time to begin exploring the possibility of lifting the ban.”

He was responding to a question from Sen. John McCain who supports such a step.

That could anger China, which is locked in a territorial standoff with Vietnam.