US vice-president Joe Biden has asked Ecuador to turn down an asylum request from National Security Agency leaker Edward Snowden, the country's president said Saturday.

Rafael Correa said he had a "friendly and very cordial" conversation with Biden, and told the vice-president that Ecuador hadn't sought to be put in the situation of deciding whether to harbor an American fugitive. Correa said Ecuador can't consider the asylum request until Snowden is on Ecuadorean soil.

"The moment that he arrives, if he arrives, the first thing is we'll ask the opinion of the United States, as we did in the Assange case with England," Correa said. "But the decision is ours to make."

Julian Assange, founder of the anti-secrecy group WikiLeaks has been given asylum in Ecuador's embassy in London.

White House spokeswoman Bernadette Meehan confirmed that the two leaders spoke by phone Friday and discussed Snowden, but wouldn't disclose any details about the conversation. It's the highest-level conversation between the US. and Ecuador that has been publicly disclosed since Snowden began seeking asylum from Ecuador.

Correa, in a weekly television address, praised Biden for being more courteous than US senators who have threatened economic penalties if Ecuador doesn't cooperate.

At the same time, Correa rebuked the Obama administration for hypocrisy, invoking the case of two bankers, brothers Roberto and William Isaias, whom Ecuador is seeking to extradite from the US.

"Let's be consistent," Correa said. "Have rules for everyone, because that is a clear double-standard here."

The US believes Snowden is holed up in a Moscow airport's transit zone. He may be waiting to see whether Ecuador or another country may grant him asylum. Snowden is charged with violating American espionage laws.

Correspondence obtained by Univision and shared with the Wall Street Journal shows that divisions over Assange have agitated Ecuador's government.

After meeting with other Ecuadorean diplomats privately, Correa declared invalid a temporary travel document that could have helped extract Snowden from his reported location in Moscow.

In a TV interview on Friday, Snowden's father expressed concerns about the involvement of WikiLeaks. "I don't want to put him in peril, but I am concerned about those who surround him," Lonnie Snowden told NBC's Today show.

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

Lonnie Snowden said he told US attorney general Eric Holder through his lawyer that his son might return home if he would not be detained before trial, could choose the location for his trial and would not be subjected to a gag order. It was not clear that Lonnie Snowden was communicating his son's views, as he also said they had not spoken since April.