Presidential lawyer Rudy Giuliani said Donald Trump's oft-repeated assertion he didn't collude with the Russians is a lie.

By declaring "Collusion is not a crime," the inconsistent Giuliani indirectly admitted Trump has been lying for over a year with his claim he didn't collude with the Russians. Giuliani's incredible faux pas comes in the wake of ex-presidential lawyer Michael Cohen's admission Trump knew beforehand about the infamous Trump Tower meeting with Russian spies last June.

If Cohen's allegation is proven true, Trump's crime is no longer collusion but a criminal conspiracy against the United States. This will be sufficient grounds for impeachment based on the high crimes and misdemeanors clause in the U.S. Constitution.

According to the Constitution, "The president, vice-president, and all civil officers of the United States shall be removed from office on impeachment for, and conviction of treason, bribery, or other high crimes and misdemeanors."

"I have been sitting here looking in the federal code trying to find collusion as a crime," said Giuliani in a TV interview. "Collusion is not a crime."

On the other hand, legal experts have repeatedly said anyone collaborating with Russia to tamper with the 2016 election can be charged with conspiracy and other crimes.

Trump has repeatedly denied there was collusion between his presidential campaign and Russia during the 2016 U.S. presidential election. On Sunday, Trump tweeted to again repeat this claim.

"There is No Collusion! The Robert Mueller Rigged Witch Hunt, headed now by 17 (increased from 13, including an Obama White House lawyer) Angry Democrats, was started by a fraudulent Dossier, paid for by Crooked Hillary and the DNC. Therefore, the Witch Hunt is an illegal Scam!"

Giuliani also took aim at Cohen, who said he's willing to tell Special Counsel Robert Mueller that Trump knew about a June 2016 meeting in Trump Tower between the president's senior campaign staff and a Russian lawyer and spy offering dirt on Democratic presidential candidate Hillary Clinton.

Before Giuliani's interviews, the intrigue about the Trump Tower meeting centered on whether the president knew the meeting was going to happen. The president previously denied foreknowledge of the meeting.

"I did NOT know of the meeting with my son, Don Jr. Sounds to me like someone is trying to make up stories in order to get himself out of an unrelated jam," tweeted Trump on July 27.

Mueller now wants to ask Trump about how involved he was in its planning. The meeting was included in a list of questions Mueller is prepared to ask Trump. Among the questions is one about when Trump first became aware of the meeting.

So far, Mueller has filed nearly 200 criminal charges against 35 defendants. Five individuals have pleaded guilty. Earlier this month, Mueller obtained an indictment against 12 Russian spies for hacking into computers belonging to the Democrats during the 2016 election. The Russians were charged with conspiracy to commit computer crimes, among others.