Jay Carney, a spokesman for U.S. President Barack Obama, said the government was "evaluating the utility" of a September meeting between Obama and Russian President Vladimir Putin. The reluctance comes as Washington expresses frustration with a decision by the Kremlin to grant asylum to Snowden, the fugitive U.S. intelligence expert.
Snowden revealed details of a U.S. surveillance program to the media and has been seeking political asylum while holed up at a Moscow airport.
A Kremlin spokesman said there was no official word from the White House on possible delays to the September meeting.
"We haven't received any changes, or any notifications," Putin's spokesman Dmitry Peskov was quoted by RIA Novosti as saying. "We don't, therefore, have any information."
Sen. John McCain, R-Ariz., a member of the Senate Foreign Relations Committee, said the decision to grant asylum to Snowden was "a disgrace and a deliberate effort to embarrass the United States."
The September meeting is meant to address a wide range of foreign policy issues. It is scheduled to occur ahead of a meeting for the Group of 20 in St. Petersburg, Russia.