French officers on Tuesday showed off a cutting-edge warship to a potential buyer — the Russian navy, whose pursuit of an amphibious assault capacity is frightening some neighboring countries.

Russia's once-mighty navy has declined severely since the fall of the Soviet Union and has no big ship with the power to anchor in coastal waters and deploy troops onto land.

Russian officials have said they were planning to make their first arms deal with a NATO country by buying a French ship like the Mistral — a 23,700-ton, 980-foot vessel able to carry more than a dozen helicopters, or land forces, hospitals or refugees, among other things.

It is the "Swiss army knife" of military ships, said Bruno Daffix, spokesman for the French Defense Ministry's export and sales agency.

The head of the Russian navy has said that, within 40 minutes, a Mistral-class vessel could put as many troops in Georgia as it took the Russian Black Sea Fleet to land in 26 hours during the nations' August 2008 war. Russia, Georgia and Ukraine all have Black Sea coastlines.

Russian military officers on Tuesday toured the Mistral, docked on the banks of the Neva, about a half-mile from the Hermitage museum.

One of two ships of that class in the French navy, the Mistral was launched in 2006 and began service in a Lebanon refugee operation.

Its captain on Tuesday dodged questions about a potential sale.

"I am a naval officer, and this issue is discussed at a different, much higher level," Didier Piaton told journalists touring the ship separately from the Russian officers.

"I hope that our visit to St. Petersburg will serve to improve relations between our two navies," he said.

The French and Russian navies may hold joint exercises before the Mistral departs this week, if weather permits, a French officer said.

Russian media reports have said a Mistral-class ship would cost Russia up to $750 million. Officials in Moscow have expressed interest in buying licenses to build several more in Russia.

In Georgia, still in tense relations with Moscow after the war, officials voiced alarm at the prospect of their giant neighbor being equipped with such a vessel.

"We strongly oppose the sale of such a ship to Russia," said Nika Laliashvili, a member of the Georgian parliament's defense affairs committee. "It poses a serious danger to Georgia."

The idea also has caused concern in Estonia, a NATO nation about 60 miles down the Baltic Sea coast from St. Petersburg.

The head of Estonia's defense forces has suggested his tiny country might have to step coastal defense operations and military infrastructure if Russia acquires ships like the Mistral and deploys them in the Baltic.

"The threat from the sea would definitely increase," Ants Laaneots said in an interview Saturday with Estonian national broadcaster ETV.

NATO officials in Brussels would not comment Monday on the possible French navy sale.

In recent years, Russia has increasingly asserted its global reach and prestige in world affairs. It has sent warships to patrol pirate-infested waters off Somalia, and in 2008 it dispatched a navy squadron to the Caribbean for joint maneuvers with the Venezuelan navy and for several port calls.

The Caribbean mission, aimed at flexing military muscle near the U.S. after the August 2008 war with Georgia, was the most visible Russian navy deployment since Soviet times.

Despite the Kremlin's ambitions, the Russian navy is working now with only a handful of seaworthy big ships and a shipbuilding industry badly crippled by the post-Soviet economic meltdown. Its single Soviet-built aircraft carrier, the Admiral Kuznetsov, is much smaller than U.S. aircraft carriers and has been plagued by mechanical problems and accidents.

Russian shipbuilders have opposed the Mistral deal, saying the government should invest in domestic production instead. Navy officials have argued that license production of Mistral-class ships would help modernize Russia's aging industries.

The French Defense Ministry's arms acquisition and sales agency has reported that French exports rose 15 percent in 2008 to $9.4 billion, thanks in part to sales of the French-Italian built FREMM multipurpose frigate to Morocco and the EC725 Cougar tactical transport helicopter to Brazil.

French military exports are expected to rise to about $10 billion this year.

Among France's recent big-ticket sales deals, Brazil has agreed to buy five French Scorpene submarines, one of them with nuclear propulsion, and 50 Cougar helicopters for about $12 billion. All would be assembled in Brazil.