Blindsided congressional Republicans worried Thursday about whether President Trump's surprise fiscal deal with the Democrats would mean more shocks are ahead on issues such as tax reform.

"We wondered if he'd back us on Obamacare repeal. He didn't do much selling to the public. Then a few days after the victory part at the White House he called it ‘mean.' Many wonder the same thing on tax reform," said one House Republican, who spoke on condition of anonymity so as not to antagonize Trump.

Though disappointed with the contours of Trump's accord with House Minority Leader Nancy Pelosi, D-Calif., and Senate Minority Leader Chuck Schumer, D-N.Y., linking a three-month hike in the debt ceiling to hurricane relief, what really rankled Republicans was how the president sprang it on them without warning.

Trump made GOP leaders look foolish and left many in the rank-and-file wondering how they'd negotiate tax reform and other thorny legislation with an administration that couldn't be trusted to keep its word. Prior to Trump's deal with the Democrats, Republicans were publicly pressing for the 18-month debt limit extension they and the White House had agreed to.

Congressional Republicans tried to put a good face on Trump's change of heart, calling it a good moment for bipartisanship and functional government. Privately, they're questioning his leadership. In the Senate, 17 Republicans voted against the deal; it passed, but with more Democratic than Republican votes, typical of fiscal agreements GOP leaders struck with former President Barack Obama.

Trump loyalists counter that extending the debt limit through Dec. 15 created a three-month window for the administration and Republicans in Congress to focus on tax reform.

But most Republicans wanted to extend U.S. borrowing power 18 months and past the 2018 elections, for the sake of both financial and political stability.

Debt ceiling votes are politically problematic for Republicans; Trump's deal means they'll have to vote to raise it at least twice before the midterm. It causes Republicans additional anxiety that they believe the Democrats will have even more leverage to dictate terms in December.

"Every vote on the debt ceiling = more you have to give to the Senate minority for 60 votes. Multiple votes = more [liberal] policy. Simple as that," Republican operative Josh Holmes said in a Twitter post. Holmes is a close confidant of Senate Majority Leader Mitch McConnell, R-Ky., and his former chief of staff.

Trump agreed to the deal on Wednesday during an Oval Office meeting with Pelosi, Schumer, McConnell and House Speaker Paul Ryan, R-Wis., interrupting Treasury Secretary Steven Mnuchin as he was reiterating the administration's demands for an 18-month debt limit hike.

Just a couple of hours earlier, Ryan said during his leadership team's televised weekly news conference that Democrats were playing politics with their demands for a three-month extension. The episode unfolded after a summer of constant warfare between Trump and Republicans in Congress, potentially exhausting whatever goodwill might have been left between the White House.

It's in this context that the two factions are attempting delicate tax reform negotiations. Repeated attempts have been made to overhaul the tax code since last accomplished 30 years ago. Any bill will require tough choices and politically tough votes — a task that grows taller every time Republicans lose more confidence that Trump will have their back and do his part.

"The way this seems to work is, when he's with you, he's with you and when he's against you, he's against you," a former House GOP aide said. "He's just reminding Congress he'll work with any suitor that fits his needs of the day."

Republicans in the House and Senate have been frustrated with the president for several months — both his antics and, in their view, amateurish leadership.

From his failure to use the bully pulpit to promote legislation partially repealing the Affordable Care Act and other elements of their shared agenda, to his obsession with the Russia investigation, to his handling of events in Charlottesville, Va., congressional Republicans are fed up.

So is Trump. He blames Republicans for undermining his agenda and not paying him due respect as the president and leader of the Republican Party.

The president's deal with Pelosi and Schumer, the first truly bipartisan agreement he's cut with Democrats since taking office, was akin to pouring gasoline on a fire. The complaints were less about the parameters of the deal, although there was grumbling, than about how Trump blindsided his supposed allies.

"The move was fine, other than screwing Ryan and McConnell after an agreement," said a House Republican who is not reflexively critical of Trump.