President Trump warned members of Congress on Wednesday not to block or delay his push to pass tax reform legislation this year after months of Democratic obstruction and Republican infighting stalled other aspects of his agenda.

"I don't want to be disappointed by Congress, do you understand me?" Trump said during a rally in Springfield, Mo., on Wednesday. The White House billed the event as a rollout of Trump's framework for the tax overhaul that congressional Republicans are expected to unveil in the coming weeks.

"I think Congress is going to make a comeback. I hope so," Trump said.

The president has spent much of the August congressional recess going after the Republicans he blames for preventing healthcare reform from advancing last month.

But Trump turned his fire to Missouri's lone Democratic senator on Wednesday, a sign that the president may soon turn up the heat on vulnerable Democrats who will run for re-election next year in red states. Republicans have expressed hope that Trump would eventually spend more time fighting with those lawmakers than with the ones he will need to fight for his agenda.

"The Dems are looking to obstruct tax cuts and tax reform, just like they obstructed so many other things," Trump said. Sen. Claire McCaskill, D-Mo., is considered to be one of her party's most at-risk incumbents up for re-election next year.

Trump issued a sweeping call for bipartisanship on tax reform in the name of creating economic opportunities, striking a tone not often heard from the confrontational president.

"Let's put, or at least try to put, the partisan posturing behind us," Trump said. "If we unite in the name of common sense and the name of common good, then we will add millions and millions of new jobs, bring back trillions of dollars and we will give America the competitive advantage it so desperately needs."