Former Watergate prosecutor said President Donald Trump's tweet about being "all alone" in the White House reminded him of Richard Nixon's last days before his resignation.

Nick Akerman said Nixon "really kept to himself" in the last days of his presidency.

He was referring to Trump's tweet on Christmas Eve that he was by himself waiting for Democrats to meet his demands on border security.

Akerman suggested that Trump was having trouble with Special Counsel Robert Mueller's progress in the Russia investigation.

A former Watergate prosecutor said President Donald Trump's tweet that he was "all alone" in the White House on Christmas Eve reminded him of Richard Nixon's final days as president before his resignation.

Trump tweeted on Monday morning: "I am all alone (poor me) in the White House waiting for the Democrats to come back and make a deal on desperately needed Border Security."

"At some point the Democrats not wanting to make a deal will cost our Country more money than the Border Wall we are all talking about," he continued. "Crazy!"

Trump had been criticizing Democrats for not giving into his demands to fund a giant wall along the US-Mexico border. The gridlock led to a partial shutdown of the federal government.

Nick Akerman, a former assistant special prosecutor during the Watergate scandal. MSNBC

Akerman, who was an assistant special prosecutor in the Watergate scandal, said Trump's tweet reminded him of Nixon's last days at the White House and suggested that Special Counsel Robert Mueller's investigation was "falling in on" Trump.

Nixon resigned from office in 1974 days after admitting that he misled the country about the White House's involvement in the break-in of the Democratic National Committee headquarters at the Watergate complex in Washington, DC, during his reelection.

Akerman told MSNBC's Chris Hayes on Wednesday: "[It's] very much the same. Nixon really kept to himself. He wound up sitting in front of the fire, and just kind of ruminating — to the point where his Secretary of Defense was so concerned, there was an alert to go out to not take any of Nixon's orders if he were to ask them to basically release any ICBMs, or missiles, against Russia."

A magnolia tree blossoms on the South Lawn. Jason Reed/Reuters

Akerman suggested that Trump's worries could be related to Mueller's investigation into the Trump presidential campaign's ties to Russia.

Referring to Trump, Akerman said: "He has got the entire wall falling in on him at this point. He's got three cooperating witnesses, three people who are very close to him: Michael Flynn, his former security adviser; [Rick] Gates who was the deputy to [Paul] Manafort and was running the campaign after Manafort left; and then you've also got Michael Cohen, his personal lawyer."

Read more: The 20 biggest Trump-Russia bombshells of 2018

In 2018, Gates pleaded guilty to conspiracy and lying to the FBI, Manafort was convicted of several counts of fraud and failure to report foreign bank accounts, and Cohen pleaded guilty in two federal criminal probes. All are cooperating in the Mueller investigation.

Akerman added: "I don't think we ever had any witnesses in the White House that were that close to Nixon. John Dean — who was the lawyer in the White House — didn't really have the closeness to Nixon that any of these three people have."

The Watergate prosecutor also said that the amount of indictments and guilty pleas Mueller had obtained so far were "remarkable," adding: "None of this is good news for the White House."

Watch the full interview here: