A White House official issued a harsh criticism of Congress' nonpartisan group of tax experts Friday, calling a recent analysis from the outfit "incredibly misleading" and "dishonest."

"There’s probably been no more dishonest or misleading study than that one that came out yesterday,” said Marc Short, the White House director of legislative affairs, referring to an analysis from the Joint Committee on Taxation published Thursday that found that the Senate GOP tax bill would raise the taxes of some middle-income groups. Short was asked about the analysis on CNN.

The Joint Committee on Taxation is a nonpartisan entity that provides tax expertise to Congress. It is controlled by Republicans, who are in the majority, and its experts received praise from Senate Republicans Thursday at the bill’s markup.

The analysis found that adding a repeal of the Obamacare individual mandate to the bill would result in some middle-income groups seeing tax increases. The mandate requires people to have insurance or pay a fine.

Republicans said Thursday, though, that the apparent tax increases could be explained by people choosing not to have healthcare coverage via an Obamacare exchange since they wouldn't be required to buy insurance, and accordingly not receiving tax credits to subsidize that purchase. The loss of the tax credits appears as a tax increase in the bill, even though it was the individual’s choice not to receive them.

A separate Joint Committee on Taxation analysis requested by Sen. Pat Toomey, R-Pa., found that the apparent middle-class tax hikes turned into tax cuts when the effect of the mandate repeal was discounted.

“It makes no sense” that eliminating the tax penalty for being uninsured would result in tax hikes, Short said.

Instead, working families would see tax cuts under the bill, he added.

The Senate aims to vote on the tax bill the week after Thanksgiving. Short said he was confident that they would have the votes to pass the legislation.

The Trump White House has derided Congress' nonpartisan scorekeepers before. Budget Director Mick Mulvaney criticized a Congressional Budget Office official in a May interview with the Washington Examiner, for which he eventually apologized.