Assange says he fears Sweden would turn him over to stand trial in USA courts for violations of the Espionage Act.
President Barack Obama defended his decision to commute Chelsea Manning's remaining prison sentence during his final press conference from the White House on Wednesday.
"With today's 209 grants of commutation, the President has now commuted the sentences of 1,385 individuals - the most grants of commutation issued by any President in this nation's history".
Mr Assange has sought refuge in the Ecuadorian embassy in London since 2012, to avoid arrest and extradition to Sweden and the US.
Leaving the confines of the embassy - which is legally sovereign Ecuadorian territory - would nearly certainly result in his immediate arrest by British police and eventual extradition to Sweden or possibly the US.
As The Telegraph notes, the U.S. has not requested extradition, but Assange believes it could happen if he makes his way to Sweden.
Obama denied that the commutation was granted because of Assange's offer one week earlier. "So the notion that the average person who was thinking about disclosing vital classified information would think that this is going unpunished I don't think would get that impression from the sentence that Chelsea Manning has served".
"I've always been willing to go to the United States, provided that my rights are respected", he said. "As of this year, it is active and ongoing", he said.
White House officials said Manning's commutation had nothing to do with Assange, even as US intelligence officials have blamed WikiLeaks for helping Russian Federation to influence last year's presidential election.
He said if it took him going to the U.S. to "flush out" the case being prepared against him, or to drop it, then "we are looking at that".
WikiLeaks had previously said it would agree to a extradition request for site founder Julian Assange if Obama granted Manning clemency, but have as yet made no statement.
"I wish Obama would have allowed the military justice system to proceed in due course, rather than short-circuiting the sentence 28 years before it was set to expire", he told CNN.