A Justice Department investigation of Assange and WikiLeaks dates to at least 2010, when the site posted thousands of files stolen by the former US Army intelligence analyst now known as Chelsea Manning.
He did say that Britain had guaranteed that the Australian would not be extradited to any country where his life is in danger.
Assange says that he faces charges under seal in the U.S. for revealing sensitive government information on WikiLeaks, though the exact charges against him remain unclear.
"The suggestion that as long as the death penalty is off the table, Mr Assange need not fear persecution is obviously wrong ..."
Moreno didn't say that his country would force Assange out of the embassy, but said the Wikileaks founder's legal team is considering its next steps.
"There is a path for Mr Assange to take the decision to exit into near freedom", Moreno was quoted by Reuters as saying in a radio interview.
Assange and the Ecuadorian embassy, which the 47-year-old has called home since 2012, have experienced tensions in recent months, with Ecuador cutting off Assange's communications in March, after he discussed topics online that could have damaged the country's diplomatic relations.
UN General Assembly rejects US-backed resolution to condemn Hamas
In a symbolic stride, the US resolution did garner support by a majority of members, but failed because it required a supermajority.
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We'll be getting Nana, a sniper-wielding senior citizen, and a particularly aggressive boar called Horatio to tag along with us. True to Far Cry form, Mickey and Lou will grace New Dawn's cover upon release, though they are far from the only new faces.
Trump nominates ex-Fox News anchor Nauert as United Nations envoy
Nauert's performance as acting undersecretary of state was notable for its lack of accomplishments or even attention to the job. Is Nauert up for the new role? According to The Guardian , the President has sought someone who will "demonstrate loyalty".
WikiLeaks' role in releasing emails hacked from the Democratic National Committee in 2016 has also been under scrutiny as special counsel Robert Mueller has investigated Russian interference in the 2016 election and whether the campaign of then-presidential candidate Donald Trump was involved.
But he said Ecuador was not about to throw Assange out.
Assange entered the embassy after two years of battling an extradition to Sweden to be questioned by prosecutors, who were considering whether charges should be brought against Assange for sexual assault.
Over the past months, the Ecuadorian authorities have been putting various restrictions on the conditions of Assange's stay in the embassy, which the whistleblower's defense called the violation of human rights.
In November a filing error revealed that Mr Assange faced charges in the U.S. - although it was not clear what those charges were.
Assange founded WikiLeaks as a whistle-blower organization in Iceland in 2006.