The Black Sea resort town of Sochi, hosting the ice-based Olympic events, and Krasnaya Polyana, 50 kilometres (30 miles) inland where the snow sports will be held, are alarmingly close to Russia's Muslim provinces of Chechnya, Ingushetia and Dagestan.

The North Caucasus region is home to a raging Islamist insurgency, where attacks by militants fueled by poverty and the ideology of global jihadism are a near daily occurrence.

"Additional security measures must be introduced during the 22nd Olympic Winter Games and the 11th Paralympics Winter Games in Sochi in 2014," Medvedev said.

Hedid not say which additional measures will be undertaken.

Analysts have warned that Sochi's proximity to the troubled areas could lead to problems during the 2014 Games.

March's twin suicide bomb attacks on the Moscow metro that killed 40 turned the global spotlight on this turbulent trio.

Authorities blamed the attacks on two women from Dagestan.

The rebels say they want to create a pan-Caucasus sharia state independent from Russia.

They view Sochi, which belongs to the mainly Christian Krasnodar region, as "occupied territory" and some want it incorporated within the separate state they want to forge, according to unofficial Islamist websites.

Deputy Prime Minister Dmitry Kozak, appointed by the Government to oversee the Games, claimed today that tightened security will not cause inconvenience for athletes and visitors to Sochi in 2014.