WASHINGTON -- A frustrated White House blasted China on Monday for allowing leaker Edward Snowden to depart Hong Kong for Russia, warning that the decision would have a detrimental effect on the already-tense relationship between Washington and Beijing.

“We find their decision to be particularly troubling,” White House spokesman Jay Carney said. “This was a deliberate choice by the government to release a fugitive, despite a valid arrest warrant. And that decision unquestionably has a negative impact on the U.S.-China relationship.”

Officials say they think Snowden remained in Russia on Monday, even as police and reporters attempted to chase after him to Cuba, where he was thought to be headed en route to Ecuador.

Julian Assange, the founder of WikiLeaks, a website that’s published classified U.S. information, said Monday that he knew where Snowden was and that his organization was helping to pay for Snowden’s travel and lodging costs.

“He’s in a safe place and his spirits are high,” Assange said during a conference call with reporters. “Due to the bellicose threats coming from the U.S. administration, we can’t go into further details at this time.”

Assange said Snowden was able to leave China through refugee documents granted to him by the Ecuadorean government, and that he’d sought legal asylum in Ecuador and Iceland with the help of WikiLeaks. Assange is a fugitive himself, hiding out in the Ecuadorean embassy in London since last June to avoid extradition to Sweden on sex-related charges.

Carney said the United States was negotiating with officials in Russia, Ecuador and other nations where Snowden might travel, but he declined to answer questions about whether the U.S. might try to force down a Russian airliner carrying Snowden.

“I think that we expect the Russian authorities to examine all the options available to them to expel Mr. Snowden appropriately,” Carney said. “And I think I can leave it at that.”

The U.S. and Russia have cooperated on several recent issues, including the Boston Marathon bombing, but they’re at odds on a series of others, from the escalating civil war in Syria to Russia’s recent ban on adoptions of its children by American parents.

Earlier Monday, while traveling in New Delhi, Secretary of State John Kerry reiterated that Russia should send Snowden back to the United States. “I would urge them to live by the standards of the law,” he said.

The United States entered its third week of a cat-and-mouse game with Snowden, 30, after the former CIA employee and National Security Administration contractor revealed himself to be the leaker of classified documents about surveillance programs. The U.S. government has charged him with various crimes under the espionage act.

“The charging of Edward Snowden is not a matter of justice, it is an attempt to intimidate any country that might be considering standing up for his rights to tell us all the truth,” Assange said. “It reflects poorly on the U.S. administration, and no self-respecting country would submit to such bullying by the U.S. in this matter.”

Carney pushed back on that notion.

“Mr. Snowden’s claim that he is focused on supporting transparency, freedom of the press and protection of individual rights and democracy is belied by the protectors he has potentially chosen: China, Russia, Ecuador, as we’ve seen,” Carney said. “His failures to criticize these regimes suggests that his true motive throughout has been to injure the national security of the United States, not to advance Internet freedom and free speech.”