U.S. Secretary of State John Kerry said Wednesday that his agency was not advising Americans against traveling to the Russian resort city of Sochi for the upcoming Winter Olympics.

"I believe that anybody who wants to go to the Olympics, which is just a great event, should go," the top U.S. diplomat told CNN in an interview.

Security for the Feb. 7-23 event has been a concern for Washington after two suicide attacks killed at least 34 people in Volgograd in southern Russia late December and threats streamed out from Islamist militants in the volatile northern Caucasus region.

President Barack Obama suggested last week that Americans check in with the State Department before making a trip to Sochi.

"We're not telling people not to go," Kerry said. "I think it will be as safe as you can make any large public event in a place where obviously we all know there have been some threats of late."

He said the United States has 140 government personnel "working under the same roof in a coordinated way with the Russians" in Sochi, including those from the Federal Bureau of Investigation, the Department of Homeland Security and the military.

"We feel that everything has been done that can be done to try to guarantee people safety and security," he said, adding his department has cautioned people to "take precautions."

Obama received Tuesday an updated briefing from his national security team about the efforts to support security for the Sochi games, in which he was assured that "all appropriate steps" had been taken to ensure the safety of Americans.

The Department of Homeland Security has warned U.S. and some foreign airlines about "toothpaste bomb" threats, as recent intelligence suggested toothpaste tubes might hold explosives and could be used to construct a bomb on board a plane, press reports said Wednesday.