Since the Nov. 3 election, Trump has privately told Republican lawmakers that he won’t back down from his position during the campaign that he would veto the annual National Defense Authorization Act if it includes an amendment to rename the bases.

A senior administration official confirmed Trump’s conversations with Republicans and his veto threat. “He’s said that,” the official said.

Trump’s stance has put in doubt legislation that had been agreed to by Republicans and Democrats in the House and the Senate. It has sent members of Trump’s party scrambling to find a path for the defense bill, which outlines military policy and funding, and put them on a collision course with Democrats.

While some Republicans are now shifting their positions to align with Trump, Democrats are refusing to budge on the agreed-to amendment, threatening passage of the legislation.