U.S Constitution says “No money shall be drawn from the Treasury, but in Consequence of Appropriations made by Law; and a regular Statement and Account of Receipts and Expenditures of all public Money shall be published from time to time.”
The president have the obligation to submit his budget request to the Congress, and Congress have to analyze it, eventually approve it or disapprove it. Congress is not an employee or even a technical advisory, is one of the legitimate powers of the federal government. It obligation is to be loyal to voters, not to approve what President proposed.
No matter whether one is on the side of the Democrats or Republicans in the discussion. No need to corrupt the sense of institutions.