U.S. Senate Republican leader Mitch McConnell on Monday proposed rules that would execute a potentially quick impeachment trial for President Donald Trump, with no guarantee that witnesses or new evidence would be allowed.A resolution McConnell unveiled on Monday would give House Democratic prosecutors and Trump lawyers 48 hours, evenly split, to present their arguments over a maximum of four days.Under the resolution, which could face a vote as early as Tuesday, lawyers for Trump could move early in the proceedings to ask senators to dismiss all charges, a senior Republican leadership aide said, a motion that would likely fall short of the support needed to succeed.