"The United States has ... been working with the Russian government through the international security advance group on Sochi preparations specifically, as we do with any host country," White House press secretary Jay Carney told reporters.
U.S. President Obama talked with Russian President Vladimir Putin Tuesday on security for the Sochi Olympics and other issues. Carney said he could not say who initiated the call.
"Let me say that, starting with the call, yesterday, that the United States has offered its full support, and any assistance to the Russian government in its security preparations for the Sochi games," Carney said. But, he stressed, "Russian authorities will be responsible for overall security at the Olympics, and the [U.S.] State Department's Bureau of Diplomatic Security has a security lead for the United States.
"We will send diplomatic security and FBI agents to [work] with host-nation security and law enforcement officials and that's standard operating procedure for large events like this, where thousands of U.S. citizens, athletes from Team USA, American corporate sponsors and members of the U.S. media are present for an extended period of time."
Carney also said "we have seen an uptick in threat reporting prior to the Olympics, which is, of course, of concern, although it is also not unusual for a major international event. And we ... have offered ... any assistance they might ... they might need to counter that threat."
The Pentagon has sent two U.S. warships "to the Black Sea as part of the prudent planning and preparations that are required for an event like this," Carney said.
Earlier this week, Russian security forces said the widow of an Islamist insurgent may have entered the Sochi security zone and be planning violence at the Winter Olympics. The opening ceremony is Feb. 7.