Meanwhile, Ecuadorean officials say Russian authorities have stymied the country's efforts to approve a political asylum application from the former National Security Agency systems analyst, according to government officials with direct knowledge of the case. Their accounts further complicate the already murky understanding of his current status.
In conceding his son's guilt, Snowden's father, Lonnie Snowden, told NBC's "Today" show that his lawyer had informed Attorney General Eric Holder that he believes his son would voluntarily return to the United States if the Justice Department promises not to hold him before trial and not subject him to a gag order.
"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," Lonnie Snowden said. The elder Snowden hasn't spoken to his son since April, but he said he believes he's being manipulated by people at WikiLeaks. The anti-secrecy group has been trying to help Edward Snowden gain asylum.
"I don't want to put him in peril, but I am concerned about those who surround him," Lonnie Snowden told NBC. "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."
Lonnie Snowden declined to comment when The Associated Press reached him Friday.
U.S. officials said their outreach to Russia, Ecuador and other countries where Snowden might travel to or seek refuge is ongoing.
"We continue to be in touch, via diplomatic and law enforcement channels, with countries through which Mr. Snowden might transit or that could serve as a final destination, also in touch, clearly, with the Russian authorities," State Department spokesman Patrick Ventrell told reporters. "We're advising governments that Mr. Snowden is wanted on felony charges and should not be allowed to proceed any further, other than necessary to return to the United States. So we continue to make that active case through diplomatic and law enforcement channels."
Ventrell said the U.S. message to Russia has been consistent.
"We don't want this to negatively impact bilateral relations. It's understandable that there are some issues raised by this, but from our perspective, based on our cooperative history of law enforcement, and especially since the Boston bombings, that there's certainly a basis for expelling Mr. Snowden," he said, citing "the status of his travel documents and the pending charges against him."
The State Department revoked Snowden's visa last weekend.
Ecuadorean officials have said publicly they cannot start considering Snowden's asylum request until he arrives either in Ecuador or in an Ecuadorean embassy.
Two government officials with direct knowledge of the negotiations said Ecuador had been making detailed plans to receive and host Snowden.
One of the officials said those plans had been thwarted by Russia's refusal to let Snowden leave or be picked up by Ecuadorean officials. The officials spoke on condition of anonymity because they weren't authorized to discuss the case by name.
Snowden intended to travel from Moscow with the intention of going on to the Ecuadorean capital of Quito but after he was held up in the Moscow airport, Ecuador asked Russia to let him take a commercial flight to meet Foreign Minister Ricardo Patino in Vietnam or Singapore, where Patino was on a pre-planned official trip, in order to be taken back to Quito by Patino, the official told The Associated Press on condition of anonymity because the official was not authorized to speak to the press.
The Russians rejected Ecuador's requests to let Snowden leave Moscow, or to let an Ecuadorean government plane pick him up there, the official said.
Ecuadorean President Rafael Correa told reporters on Thursday that Snowden was "in the hands of the authorities" in Russia.
But Russian authorities have said Snowden is outside Russian control in a transit area of the Moscow airport, which is technically not Russian territory.
Edward Snowden is charged with violating U.S. espionage laws for leaking information about NSA surveillance of Internet and telephone records to detect terrorist plots.