Sen. Rand Paul criticized the newly released Republican tax reform framework Monday, citing an outside analysis that the plan authored by the Trump White House and congressional GOP leadership could raise taxes on many middle-class households.

"This is a GOP tax plan?" the Kentucky Republican tweeted.

This is a GOP tax plan? Possibly 30% of middle class gets a tax hike? I hope the final details are better than this. https://t.co/lcjkI4YRz8 — Senator Rand Paul (@RandPaul) October 2, 2017

Paul linked to an analysis published Friday by the Tax Policy Center, a document that the White House and Hill Republicans criticized and pushed back against over the weekend.

On Sunday, for instance, Office of Management and Budget Director Mick Mulvaney said on CNN that he wouldn't "put very much weight on that particular" analysis, suggesting, inaccurately, that an adviser to former Vice President Joe Biden works at the think tank.

Rep. Kevin Brady, the Republican chairman of the House Ways and Means Committee, accused the Tax Policy Ceneter of bias Monday, saying that "their analysis was a work of fiction that Stephen King would have been proud of."

Brady added that he was friends with Paul and noted that the think tank had "savaged" Paul's presidential campaign tax plan.

Republicans have pledged that the eventual tax bill will make the tax code more progressive than it is today, even if the framework released thus far does not clearly indicate how that goal will be accomplished.

Paul has called on Republican Party to more aggressively pursue tax cuts rather than a comprehensive reform plan.

Recently, he has been an obstacle to President Trump's agenda, vocally opposing the Senate's latest plan to overhaul Obamacare. Paul is a "friend of mine but he is such a negative force when it comes to fixing healthcare," Trump tweeted last month.