I believe this was discussed by the Supreme Court in the past. Congress tried to give the President a line item veto, but the Supremes stated that they could not change it without a Constitutional Amendment.
If anyone remembers this please chime in. If they know different also chime in.
That’s how I remember it - line item veto was written into the law by Congress - Supreme Court ruled it unconstitutional, something about the House having ultimate authority over specific spending bills.....