The top Senate tax writer cast doubts Wednesday on the prospect of Congress passing the vague, new tax cuts that President Donald Trump floated this week.

The Republican-controlled legislative branch is "highly unlikely" to approve the proposed 10 percent tax cut for the middle class this year, Senate Finance Committee Chairman Orrin Hatch told reporters, according to Politico. While the retiring Utah Republican said it would "take a real monumental effort" to push a tax bill through, he added that "you can't count out the Congress."

As Republicans try to juice voter enthusiasm and hold control of Congress, Trump proposed a tax cut that appeared to catch congressional leaders and even some White House officials off guard. On Monday, he said "we're putting in a resolution some time in the next week and a half to two weeks" to give middle-income people a 10 percent tax cut "on top of" the decreases the GOP passed last year. The Republican tax plan has sparked criticism for benefiting corporations and the wealthy more than middle-income people.

Hatch's House counterpart, Ways and Means Committee Chairman Rep. Kevin Brady, said Tuesday that he will work with the Trump administration "to develop an additional 10 percent tax cut focused specifically on middle-class families and workers, to be advanced as Republicans retain the House and Senate." Still, passing such a bill before the end of the year appears unlikely.