President Donald Trump once again reverted to calling the investigation into the Russian attack on the 2016 presidential election a "hoax."

On Sunday, Trump issued a tweet blaming President Barack Obama for not doing "something" about Russian efforts to disrupt the election. The president also asked why Obama "didn't tell our campaign," concluding that "it is all a big hoax."

The president is not telling the truth. Again.

First, the Obama administration issued a report in October 2016 detailing what they knew about Russian efforts to hack the DNC and use the stolen material to mount a disinformation campaign to sway American voters. The New York Times broke the story on Friday, October 7.

The piece would have likely made front page news, however, it was pushed to page two. Guess what took its place? Trump's infamous Access Hollywood tape in which he can be heard saying he likes grabbing women by the p*ssy, leaked that same afternoon and monopolized the headlines.

Second, Trump was told of Russia's hacking of the DNC prior to the second presidential debate, which took place on Sunday, October 9. He was first briefed on the matter in August but maintained his personal denial of the facts, deflecting the blame from Russia to China or "somebody on their bed that weighs 400 pounds."

“I don't think anybody knows it was Russia that broke into the DNC. She's saying Russia, Russia, Russia, but I don't -- maybe it was. I mean, it could be Russia, but it could also be China,” he told NBC’s Lester Holt on Sept. 26. “It could also be lots of other people. It also could be somebody sitting on their bed that weighs 400 pounds, OK?”

The president's campaign knew what was happening and chose to deny it, ignore it, and lie about it.

And while it's true that Obama and most of the political world thought Hillary Clinton was going to win the election, it was Senate Majority Leader Mitch McConnell who threatened to make Obama's life hell if he brought any more public attention to the issue of Russian election hacking.

For its part, the Obama White House brooded over what to do with this information without looking like it was trying to sway the election toward Clinton. Obama did, however, order a “full review” of Russia's actions, which the 44th president wanted to be completed by the time he left office on January 20, 2017.

In fact, according to a December 2016 report in the Washington Post, McConnell expressed doubts over the veracity of CIA's conclusion that Russia was interfering in the election.

In September, during a secret briefing for congressional leaders, Senate Majority Leader Mitch McConnell (R-Ky.) voiced doubts about the veracity of the intelligence, according to officials present.

The Trump campaign vigorously denied the allegations.

"These are the same people that said Saddam Hussein had weapons of mass destruction. The election ended a long time ago in one of the biggest Electoral College victories in history. It’s now time to move on and ‘Make America Great Again,’" the campaign said in a statement.

Trump has continued to call Special Counsel Robert Mueller's investigation into Russian election meddling a "rigged witch hunt."

Fast forward to last week. Trump met with Russian President Vladimir Putin in Helsinki on July 16 in a closed-door setting with no notetaking or recording. During a press conference after their chat, Trump said he trusts American intelligence but Putin was "very strong and powerful" in his denial of having anything to do with the 2016 hacks.

"I don't see any reason why it would be" Russia, Trump also said.

The next day, the president attempted to walk back his conclusion. Reading from prepared remarks, Trump said he "misspoke" and meant to say "I don't see any reason why it wouldn't be" Russia. He added that he has full faith in his intelligence agencies as the power went out in the White House.

During the same meeting, Trump answered "no" when asked by a reporter if Russia is still targeting the United States and its elections.

On Friday, Director of National Intelligence Dan Coats was informed, during a live interview with MSNBC's Andrea Mitchell, that Trump had invited Putin to the Washington D.C. for a second summit this fall. Coats has maintained his assertion that Russia is still trying to disrupt American elections, much to the chagrin of the White House.