
Asked in an interview with CNN whether he would advise friends to go to the Games amid security concerns, he said: "I'd tell them that I believe Sochi is safe and that there are always some risks in these large international gatherings."
Two suicide bombings in the Russian city of Volgograd last month - killing 34 people - led to renewed concerns about the risk of an attack during the Olympics.
Last week, Islamic militants released a video claiming responsibility for the two deadly suicide bombings in Volgograd in December which killed 34 people and injured more than 100.
"The Russian authorities understand the stakes here," said President Obama, who is not going to the Games.
"We've looked at their plans.
"I think we have a good sense of the security that they are putting in place to protect not only the athletes themselves, but also visitors there.
"I don't want to completely discount those.
"But as we've seen here in the United States, at the Boston Marathon, there were some risks if you have lone wolves or small cells of folks who are trying to do some damage."

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On Monday (January 27), it emerged British officials have warned in a threat assessment for the Games that terrorist attacks in Russia before or during Sochi 2014 are "very likely to occur".
The Sochi Games are the biggest security operation in Olympic history, with more than 30,000 police and Interior Ministry troops deployed to the area.
FIB agents are also in the Winter Olympic host city to provide support to the Russians.
The Opening Ceremony of the Olympics is due next Friday (February 7).
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