Sen. Marco RubioMarco Antonio RubioThe Memo: Biden's immigration problems reach crescendo in Del Rio Democrats face bleak outlook in Florida The Hill's 12:30 Report - Presented by Facebook - Dems attempt to tie government funding, Ida relief to debt limit MORE (R-Fla.) said Sunday that it's in President TrumpDonald TrumpGraham says he hopes that Trump runs again Trump says Stacey Abrams 'might be better than existing governor' Kemp Executive privilege fight poses hurdles for Trump MORE's best interest to let special counsel Robert MuellerRobert (Bob) MuellerSenate Democrats urge Garland not to fight court order to release Trump obstruction memo Why a special counsel is guaranteed if Biden chooses Yates, Cuomo or Jones as AG Barr taps attorney investigating Russia probe origins as special counsel MORE complete his investigation into Russian interference in the 2016 election.
Rubio, appearing on "Fox News Sunday," echoed a number of his Republican colleagues in defending the special counsel in the face of Trump's call last week for Attorney General Jeff SessionsJefferson (Jeff) Beauregard SessionsOvernight Hillicon Valley — Apple issues security update against spyware vulnerability Stanford professors ask DOJ to stop looking for Chinese spies at universities in US Overnight Energy & Environment — Democrats detail clean electricity program MORE to end the Mueller investigation.
Rubio said the "best thing that can happen" for Trump and the country is for the investigation to "run the course and for all the truth to come out."
He added that he believes any strong evidence that the president's campaign directly colluded with Russia would have leaked by now.
Asked if he believes Trump should sit for an interview with the special counsel, Rubio said he wouldn't "pre-judge" if the president declined an interview.
"There are plenty of people who are innocent whose lawyers would tell them not do sit down and answer questions from a prosecutor because there's all sorts of other problems involved in that," Rubio said.
Trump has said he'd like to speak with Mueller, but his attorneys have cautioned against it. The two sides are in negotiations about a potential interview, with Mueller reportedly offering to limit his questioning.
As part of a recent escalation of attacks on the Mueller investigation, Trump tweeted last Wednesday that Sessions "should stop this Rigged Witch Hunt right now, before it continues to stain our country any further."
The tweet drew pushback from a number of Republicans, and a significant bloc of Democrats. However, some Republicans, including Vice President Pence, have called on Mueller to conclude his investigation promptly.
The New York Times reported that Mueller is reportedly looking at Trump's use of Twitter as part of an investigation into whether the president obstructed justice.