Donald Trump was accused of inviting further interference in US elections on Friday after he suggested he would be open to accepting "dirt" on political opponents from foreign powers.
The US president said he would gladly take incriminating information about an opponent from adversaries such as Russia, flying in the face of his own FBI director's recommendations.
Leading Democrats were quick to seize on the comments, suggesting Mr Trump had not learned any lessons from 2016 and was inviting Russian help in the 2020 presidential election.
Senate Minority Leader Chuck Schumer said Mr Trump’s suggestions were “disgraceful” and “shocking” as he took took to the Senate floor on Thursday. “It’s as if the president had learned absolutely nothing in the past two years”, he said, referring to the federal investigation into potential Russian interference in the 2016 election.
The role of Mr Trump's eldest son, Donald Trump Jr, in organising a 2016 meeting with a Russian lawyer offering negative information on Hillary Clinton was a focus of the inquiry.
Nancy Pelosi, the Democratic leader of the House of Representatives, said: “The president gave us evidence once again he does not know right from wrong".
Both Mrs Pelosi and Mr Schumer called for new legislation making it a legal requirement for candidates to report any efforts by foreign governments to influence American elections.
Under US law it is already a crime for a candidate to accept money or anything of value from foreign governments for the purpose of winning an election, however there is some dispute among legal scholars whether incriminating information constitutes a thing of value.
Mrs Pelosi added that “everybody in the country should be totally appalled” by Mr Trump’s comments, made during an ABC News interview broadcast on Wednesday night.
Asked what he would do if Russia, China or other foreign governments offered his 2020 re-election campaign information on an opponent, he said: "There's nothing wrong with listening... I think I'd want to hear it," describing it as opposition research.
Mr Trump also scoffed at the idea of calling the FBI, saying “life doesn’t work that way,” adding “the FBI director is wrong.”
However he did concede that he would call the agency “if I thought there was something wrong” with the information.
Most Republicans remained silent on the issue however senator Lindsey Graham, a close ally of Mr Trump, issued a public rebuke. “I believe that it should be practice for all public officials who are contacted by a foreign government with an offer of assistance to their campaign - either directly or indirectly - to inform the FBI and reject the offer,” he said.
Mr Trump defended his willingness to accept campaign help from foreign governments in a series of tweets, equating it with the diplomatic meetings he holds with heads of state.
"I meet and talk to 'foreign governments' every day," he said.
"I just met with the Queen of England (UK), the Prince of Wales, the PM of the United Kingdom... Should I immediately...call the FBI about these calls and meetings?"