Talks between the UK and Ecuador over the future of Julian Assange at its London embassy have broken down, the South American country's Foreign Minister said.
Maria Fernanda Espinosa suggested British officials had been unwilling to negotiate over the Wikileaks founder's potential release.
Earlier this month, a judge upheld an arrest warrant issued when Mr Assange skipped bail as he fought extradition to Sweden in 2012.
Statement on ruling: We are surprised. Judge went well outside what the parties presented in court. This seems to have led to many factual errors in the judgment. US DoJ confirmed to Reuters again yesterday that its case is ongoing. There are 3 months to appeal judge's decision.
-- Julian Assange ? (@JulianAssange) February 13, 2018
The 46-year-old has been at the embassy ever since as he fears extradition to the United States for questioning over the activities of WikiLeaks if he leaves.
Ms Espinosa said of the failed talks: "To mediate you need two parties, Ecuador is willing, but not necessarily the other party."
Ecuador said it would continue to protect Mr Assange's rights, however there was a risk to his physical and psychological well being after spending nearly six years in the building as a "refugee".
The country has assessed more than 30 similar cases in a bid to break the deadlock, including that of British-Iranian citizen Nazanin Zaghari-Ratcliffe, who is in prison in Iran accused of spying.
This included options for granting diplomatic immunity, although Ecuador said it would continue to respect the UK's laws.
In November, Ms Espinosa said Mr Assange had been granted Ecuadorian citizenship.
The Foreign Minister said Ecuador was trying to make Mr Assange a member of its diplomatic team, which would grant him additional rights under the Vienna Convention on Diplomatic Relations - including special legal immunity and safe passage.
Last week, former Cabinet minister Sir Patrick McLoughlin asked the Home Office when action will be taken over Mr Assange's case during Commons questions.
He said the first three years of Mr Assange's five-year stay in the embassy had cost the Metropolitan Police an additional £11 million.