"In the meantime, the never-ending Witch Hunt, led by 13 very Angry and Conflicted Democrats (& others) continues into the mid-terms!" he said, unleashing a series of tweets on completing 500 days in office.
"It was a mistake, I swear to God, it was a mistake", Giuliani said in an interview with CNN on Monday night, after The New York Times reported a leaked 20-page letter to Mueller that explained Trump dictated the statement.
"And so I don't think there's any rationale to sit down, nor is there any rationale to subpoena the president to sit down".
Senate Minority Leader, Senator Chuck Schumer, slammed Trump for such a tweet, asserting that the president has no such power.
A special counsel is investigating Russia's role in the 2016 election, and whether Trump obstructed justice.
"I think it would probably get answered by, "gosh, that's what the Constitution says".
Giuliani, who has been serving as Mr. Trump's lawyer amid the Russian Federation scandal, says Wednesday in Israel that Mueller's team includes "13 highly partisan Democrats".More news: French Open 2018: Fernando Verdasco downs Grigor Dimitrov in straight sets
The investigation has so far made no allegations against the president himself.
When asked, Lee declined to speculate about the motivations of Trump or his legal team in bringing up the pardon power.
Speaking on American ABC's This Week program, Mr Giuliani added: "It would be an open question".
Giuliani said there was no choice but to cancel the June 12 summit after Kim insulted the US vice-president and national security and threatened nuclear war. After a year of investigations, Mueller hasn't produced proof of any such collusion and appears to have shifted toward a search for evidence that Trump impeded the investigation.
Ryan also rejected Trump's claim that FBI investigators illegally placed an informant inside his campaign. In that tweet, he insisted that "we play the game because I, unlike the Democrats, have done nothing wrong!"
The former chairman of President Donald Trump's presidential campaign is facing accusations of trying to tamper with witnesses in his ongoing criminal cases.
But Mueller is a Republican who was named special counsel by Deputy Attorney General Rod Rosenstein, who is also a Republican appointed by Trump.