(Adds comment from Swedish government official)
QUITO, Nov 17 (Reuters) - Ecuador's foreign minister said WikiLeaks founder Julian Assange should receive guarantees that he will not be extradited if he faces justice in Sweden after four years of living in the South American nation's embassy in London.
Assange, who enraged Washington by publishing a flood of secret U.S. diplomatic cables, fled to the embassy fearing that Sweden could end up sending him on to the United States where he could face prison for leaking U.S. secrets.
"If we can obtain guarantees that Mr. Assange will not face extradition to the third country, I think it's fine for him to face Swedish justice - if there are charges, because there are still no charges," Foreign Minister Guillaume Long said in an interview on Wednesday with an Ecuadorean radio station.
But a Swedish government official said on Thursday it would not be possible to offer Assange or Ecuador a guarantee, as Sweden has not been asked by the United States to extradite him.
"It would actually breach the constitution if the government would give such a guarantee in advance," Cecilia Riddselius of the Swedish Ministry of Justice's Division for Criminal Cases and International Judicial Co-operation said.
Swedish Chief Prosecutor Ingrid Isgren posed questions through an Ecuadorian prosecutor at the embassy earlier this week, but did not give any comment on the case. who has repeatedly denied the rape allegation, sought refuge in Ecuador's embassy in August 2012. He is wanted in Britain for breaching bail.