Following the lead of his lawyers, President Donald Trump on Tuesday said collusion "is not a crime."

"Collusion is not a crime, but that doesn't matter because there was No Collusion," Trump tweeted Tuesday.

The tweet, alluding to the federal investigation into Russian interference in the 2016 election that includes possible collusion between Trump's campaign and Moscow, came a day after the president's personal lawyer, Rudy Giuliani, in a media blitz, began making the same defense. Giuliani appeared on multiple television networks Sunday and Monday to stress the president's innocence and add that "collusion is not a crime."

For months, Trump had insisted that there was "no collusion" between his campaign and Russia. As recently as Sunday, the president went on a tweetstorm, writing that “There is No Collusion!”

Now, however, the president and his personal lawyer are shifting their defense to include the idea that collusion, even if it did occur, isn't illegal.

In fact, there is no statute covering "colluding" with a foreign power. It is illegal, however, to conspire to violate laws, including ones barring foreign participation in elections.

In an indictment this month, special counsel Robert Mueller accused 12 Russian intelligence officers of conspiracy to hack computers and defraud the United States, alleging that people “known and unknown to the grand jury” participated in that conspiracy.

Meanwhile, Jay Sekulow, another of Trump's personal lawyers, told Fox News on Tuesday that Mueller's Russia investigation will find no evidence of collusion, before also stating that collusion is not a crime.

“There's not any evidence of any collusion here involving our client and the Russians,” Sekulow told Fox, adding that he and his team of lawyers had looked through 1.4 million documents related to the Trump campaign and the special counsel investigation.

“Rudy Giuliani was correct — collusion is not a crime,” Sekulow said. “Well, that's not just technically correct. I mean that’s actually the law. But there’s no violation of law, statute, rule or regulation that we have seen after reviewing this case for a year, and I think Bob Mueller will come to the same conclusion.”

The evolving argument from Trump and his lawyers comes just a week after Michael Cohen, Trump's former personal attorney, asserted that Trump knew in advance about a meeting at Trump Tower in June 2016 between his son Donald Trump Jr. and a Russian lawyer. Then-Trump campaign chairman Paul Manafort and Trump's son-in-law, Jared Kushner, also participated in that meeting.

A knowledgeable source told NBC News that Cohen is willing to inform Mueller that Trump Jr. told his father about the meeting, contradicting Trump Jr.'s congressional testimony in May 2017. Trump has also asserted he didn't know about the meeting.

On Monday, Giuliani, in a series of confusing media interviews, also accused Cohen, as well as Cohen's lawyer, Lanny Davis, of incorrectly describing the attendees of various meetings that involved top figures in the Trump campaign around that same time period. He also appeared to suggest that another meeting had occurred at some point before the Trump Tower meeting, in which participants purportedly discussed "strategy" for the meeting with the Russians, before attempting to clarify later in the day that there had been no strategy session.

A source familiar with the secret testimony of key Trump Tower meeting participants to the House and Senate Intelligence Committees told NBC News that none of them ever raised the issue of a strategy session to get ready for the meeting. Neither was such a session mentioned in their testimony to the Senate judiciary committee, which has been made public.