Donald Trump offered Julian Assange a pardon if he said Russia was not involved in a leak of Democratic Party emails, a court has heard.
The WikiLeaks founder's barrister brought the subject up at Westminster Magistrates' Court ahead of an extradition hearing next week.
It refers to a series of messages that were embarrassing for the Democrats and Hillary Clinton's presidential campaign in 2016.
The emails were hacked before being published by WikiLeaks.
Edward Fitzgerald QC said there was evidence alleging that former US Republican congressman Dana Rohrabacher went to see Assange while he was still at the Ecuadorian embassy in central London in August 2017.
A statement from Assange's lawyer, Jennifer Robinson, showed "Mr Rohrabacher going to see Mr Assange and saying, on instructions from the president, he was offering a pardon or some other way out if Mr Assange... said Russia had nothing to do with the Democratic National Committee (DNC) leaks", Mr Fitzgerald said.
The evidence is admissible, District Judge Vanessa Baraitser said.
The White House dismissed the allegation as a "complete fabrication and a total lie".
Press secretary Stephanie Grisham said: "The president barely knows Dana Rohrabacher other than he's an ex-congressman.
"He's never spoken to him on this subject or almost any subject. It is a complete fabrication and a total lie. This is probably another never ending hoax and total lie from the DNC."
Mr Rohrabacher issued a statement, in which he said there was "a lot of misinformation floating out there regarding my meeting with Julian Assange".
He continued: "At no time did I talk to President Trump about Julian Assange. Likewise, I was not directed by Trump or anyone else connected with him to meet with Julian Assange.
"At no time did I offer Julian Assange anything from the president because I had not spoken with the president about this issue at all."
Mr Rohrabacher added: "However, when speaking with Julian Assange, I told him that if he could provide me information and evidence about who actually gave him the DNC emails, I would then call on President Trump to pardon him. At no time did I offer a deal made by the president, nor did I say I was representing the president."
The US wants Assange to face 18 charges, including conspiring to commit computer intrusion over the publication of US cables a decade ago.
He is accused of working with former US army intelligence analyst Chelsea Manning to leak hundreds of thousands of classified documents, and could face up to 175 years in jail if found guilty.
A group of doctors and psychologists said this week that he is in a "dire state of health".
The 48-year-old appeared by videolink from Belmarsh prison, wearing dark tracksuit bottoms and a brown jumper over a white shirt.
He held a stack of papers, and spoke only to confirm his name and date of birth.
The Australian has been on remand at the category A prison in southeast London since last September after serving a 50-week sentence for breaching his bail conditions while at the Ecuadorian embassy.
He entered that building in Knightsbridge to avoid extradition to Sweden over sex offence allegations he has always denied and which were subsequently dropped.
His extradition hearing is due to begin at Woolwich Crown Court on Monday.
(SKY NEWS)