“I pray that Acting Attorney General Rosenstein will bring an end to alleged Russia Collusion investigation," Dowd said, calling the probe "manufactured."
Lankford said on "This Week," "The clearest thing that I can explain from that is the president’s exceptionally frustrated, that he wants to be able to see this investigation come to an end. He has stated over and over again there was no collusion."
"So it’s not that Mueller has found nothing, it’s that the president seems to be very, very frustrated that they have not connected anything to him and ... he wants to be able to move on," the Oklahoma senator said.
Lankford added that Dowd’s comments were nothing more than talk typical from any attorney.
"What I read yesterday was what a typical attorney puts out at every stage during every investigation saying, 'This is wrapped up. We should be done,'" Lankford said. "So it’s not different than what an attorney does typically."
The Oklahoma Republican sits on the Senate Intelligence Committee, which is conducting its own probe of Russian meddling in the 2016 U.S. election and possible ties to Trump associates. He said the special counsel should be allowed to finish his investigation.
"I would say the best thing the special counsel can do is to finish the investigation, gather all the information that’s needed [and] come to a conclusion so the American people can make their own decisions,” Lankford said. "What I have said over and over again as well is it’s best for the special counsel to be able to go through their process. It’s best for the president, best for the presidency for this to be resolved and to be finished one way or the other."
Lankford added that he has had concerns about some of the people on Mueller's investigative team.
“It is odd the number of Democrats that he’s put on board his team. That does raise some flags in some sense there,” the senator said, adding that Mueller seems to have addressed the issue of any possible bias in the probe.
Mueller "seems to be moving on from there," Lankford said.