Russia fired three long-range missiles and pronounced its nuclear deterrent strong in an extraordinary show of force experts said had not been seen anywhere since the days of the Cold War.

Two of the missiles were fired Sunday from nuclear submarines in the Asian and European extremes of the sprawling country while a third was watched by President Dmitry Medvedev on land in northwest Russia, news agencies reported.

It was the second Russian intercontinental ballistic missile (ICBM) test in as many days and the latest in a series of high-profile military exercises of conventional land, sea and air forces as well as strategic nuclear units.

"This shows that our deterrent is in order," Medvedev was quoted by RIA Novosti news agency as saying after Sunday''s missile launches.

"We will of course be introducing new types of forces and means into the military," he added, without elaborating.

Independent military analyst Pavel Felgenhauer said the exercises reflected Russia''s determination to prepare for major military conflict.

"This was a dry run for a war with the United States," Felgenhauer said of the missile launches, part of major military manoeuvres billed "Stability 2008" involving all military branches.

"These are the biggest strategic war games in more than 20 years. They are on a parellel with those held in the first half of the 1980s. Nothing of the sort has been seen either in Russia or the United States since then," he said.

Russian navy spokesman Igor Dygalo confirmed the near-simultaneous ICBM test-launches from submarines in the Sea of Okhotsk north of Japan and the Barents Sea northeast of Norway, saying they had been planned well in advance.

Speaking to AFP from northwest Russia, Dygalo admitted it was unusual for the navy to conduct three ICBM test launches in two days -- a submarine in the Barents Sea also fired a missile Saturday -- and called the tests successful.

"The missiles hit right on target," he said. News agencies said the missiles launched from the Barents Sea and the secret base at Plesetsk hit targets on the Kamchatka peninsula thousands of kilometres (miles) to the east.

The missile fired from the Sea of Okhotsk hit on target near Kanin Nos, a finger of land jutting into the White Sea in extreme northwest Russia, the reports said.

The Sineva missile launched Saturday -- an exercise also watched by Medvedev from aboard an aircraft carrier -- travelled more than 11,500 kilometres (7,145 miles) in what the Russian president claimed was an all-time distance record.

The missile tests came a day after Russia announced that a small naval flotilla led by the nuclear battlecruiser Pyotr Veliky (Peter the Great) had paid a call at the Libyan port of Tripoli.

The ships, including a submarine destroyer and support vessels, were to conduct exercises at unspecified locations in the Mediterrannean Sea before heading toward Venezuela for joint exercises there in November, officials said.

Two Russian Tupolev-160 strategic bombers -- each capable of carrying 12 cruise missiles armed with single 200-kiloton nuclear warheads -- carried out exercises in Venezuela last month.

Last week, Japan scrambled a pair of US-made F-15 fighters to intercept and escort Russian bombers on patrol near, but not inside, Japanese territorial waters.

The Kremlin, alarmed and angered over new US missile defence plans in eastern Europe and the expansion of the US-led NATO alliance into countries once allied with Moscow, has stressed for a year that it will respond in kind.

Washington has shrugged off Russian moves over the past 18 months to resume strategic bomber patrols around the world and reactivate use of its navy to project power on the seas, questioning if the hardware was up to the task.