Cars are parked at a parking lot in front of the Moscow Sheremetevo airport on June 23, 2013. Former NSA contractor Edward Snowden arrived on June 23, 2013 in Russia from Hong Kong. The United States demanded early Monday that Snowden, charged with revealing vast US surveillance, should "not be allowed to proceed further" overseas as he landed in Moscow en route to Ecuador

The United States demanded early Monday that Edward Snowden, charged with revealing vast US surveillance, should "not be allowed to proceed further" overseas as he landed in Moscow en route to Ecuador.

State Department spokeswoman Jen Psaki, travelling with Secretary of State John Kerry in India, confirmed that the United States revoked Snowden's passport due to "felony arrest warrants" against the former government contractor.

"Persons wanted on felony charges, such as Mr Snowden, should not be allowed to proceed in any further international travel, other than is necessary to return him to the United States," Psaki said.

Psaki said the revocation of Snowden's passport was "routine and consistent with US regulations" in light of the charges against him.

"Such a revocation does not affect citizenship status," she said.

Snowden, who fled to Hong Kong to reveal sensational details of cyber-espionage by the United States, flew to Russia on a commercial flight and was requesting asylum from Ecuador's left-leaning government.