Evidence from Donald Trump's former lawyer about Russian collusion with his presidential campaign team could lead to his impeachment, Richard Nixon's former White House counsel has claimed.
John Dean made the comments after the publication of a legal memo from Robert Mueller, who is leading the investigation into Moscow's influence on the election.
It is mainly to guide sentencing for crimes Michael Cohen, Mr Trump's former personal attorney has admitted to.
It says that Mr Cohen provided information about his own contacts with Russian interests during the campaign and "discussions with others in the course of making those contacts" and also "information about attempts by other Russian nationals to reach the campaign".
Mr Mueller also claims that Mr Cohen had admitted making false statements about a Trump property deal, out of loyalty to the president and admitted to paying hush money to two women who alleged they had affairs with Mr Trump. This could amount to a violation of US campaign finance laws.
Mr Dean told CNN that the US Congress had enough evidence to impeach the US leader.
The former White House counsel was jailed for his role in the Watergate scandal which brought down the presidency of Richard Nixon in 1974, after becoming a witness for the prosecution.
At the height of the scandal about an attempt to bug the offices of the Democratic National Committee in the 1972 election year, he advised Mr Nixon as he fired Archibald Cox, the special prosecutor appointed to investigate "all offenses arising out of the 1972 election… involving the president, the White House staff or presidential appointments".
Comparing that time to Mr Trump's current position, Mr Dean said: “I don’t know that this will forever disappear into some dark hole of unprosecutable presidents,” Mr Dean said. “I think it will resurface in the Congress. I think what this totality of today’s filings show that the House is going to have little choice the way this is going other than to start impeachment proceedings.”
The White House has insisted Mr Mueller's memo revealed nothing of value.
“The government’s filings in Mr Cohen’s case tell us nothing of value that wasn’t already known,“ press secretary Sarah Huckabee Sanders said. ”Mr Cohen has repeatedly lied and as the prosecution has pointed out to the court, Mr. Cohen is no hero.”
Calls for Trump’s impeachment have nonetheless ramped up after Mr Cohen pleaded guilty to “knowingly and willfully“ making ”a materially false, fictitious and fraudulent statement and representation” to the House and Senate Intelligence committees in 2017 regarding a Trump real estate project in Moscow.
After the Democrats have taken back control of the House of Representatives, it is now possible for an impeachment process to be initiated but it would take some time and political persuasion.