THE father of fugitive US intelligence leaker Edward Snowden has revealed he is trying to broker a compromise with the government that could bring his son back to the United States.

In a letter to the Justice Department, Lonnie Snowden said through his lawyer that his son wanted "ironclad assurances" he would not be held in jail before trial or subjected to a gag order, and would be allowed to choose where he would be tried on federal espionage charges.

The elder Snowden said the offer could end the impasse that has kept his 30-year-old son stuck in the transit zone of a Moscow airport and raised tensions between the US and other countries, including China, Russia and Ecuador, where the former National Security Agency contract employee is seeking political asylum.

"We believe you share our objective of securing Edward's voluntary return to the United States to face trial," Washington DC attorney Bruce Fein wrote to Attorney General Eric Holder on behalf of Snowden's father.

Lonnie Snowden, Fein wrote, "is reasonably certain that his son would voluntarily return to the United States if there were ironclad assurances that his constitutional rights would be honoured, and he were provided a fair opportunity to explain his motivations and actions to an impartial judge and jury".

If any of the conditions were "dishonoured," Fein added, then the prosecution "would be dismissed".

Justice Department officials did not comment on the proposal.

Meanwhile, the president of Ecuador demanded that the US stop suggesting that the small Andean country is provoking the situation by offering to shield Snowden from US justice, much as it has protected Australian WikiLeaks founder Julian Assange.

For the last year, Assange has lived in Ecuador's embassy in London after he was granted sanctuary.

"It is outrageous to try to delegitimise a state for receiving a petition for asylum," Ecuador President Rafael Correa said in a speech in Ecuador.

Correa contended that the news media at first welcomed Snowden's leaks about secret US programs to collect phone logs and emails but later suggested the actions were treasonous.

"What a joke!" the president said in a tweet.

The media, he said, are "making everyone forget the terrible things that he denounced in front of the American people and the entire world".

Correa added that, for the asylum request to be processed and approved, Snowden first must find his way to Ecuador's embassy in Moscow or to Ecuador.

"We don't know how it'll be resolved," he said.

Officials in Hong Kong, where Snowden flew when he left Hawaii, said they remained concerned about his claims that the NSA had hacked into Hong Kong's computer systems.

In the future, they said, Snowden will no longer be permitted in Hong Kong.

"We are very disappointed," said Lai Tung-kowk, Hong Kong's secretary of security.

"We hope the US government will as soon as possible give a full answer and explanation to the Hong Kong people."

US State Department officials said they were concerned about their worsening relationships with Hong Kong and Ecuador.

"These issues have an impact when we have a breakdown on co-operation," Patrick Ventrell, a spokesman, said in response to Hong Kong's statements.

Regarding Ecuador, Ventrell said it "would not be a good thing" if the country granted Snowden asylum.

"That would have grave difficulties for a bilateral relationship," he said.

Lonnie Snowden, who has not spoken with his son since April, said on NBC's Today show: "I love him. I would like to have the opportunity to communicate with him. I don't want to put him in peril, but I am concerned about those who surround him.

"I think WikiLeaks, if you've looked at past history, you know, their focus isn't necessarily the constitution of the United States. It's simply to release as much information as possible."

"At this point I don't feel that he's committed treason. He has in fact broken US law, in the sense that he has released classified information," Lonnie Snowden told NBC.

"And if folks want to classify him as a traitor, in fact he has betrayed his government. But I don't believe that he's betrayed the people of the United States."