ASHKHABAD -- Turkmenistan declined to take part in military exercises on the disputed oil-rich Caspian Sea on Tuesday, citing its neutral status and dubbing the manoeuvres "pointless".

Three states bordering the Caspian Sea -- Russia, Azerbaijan and Kazakhstan -- are participating in the large-scale exercises, which will involve more than 60 warships and 10,000 men over two weeks until August 15.

Representatives from both Turkmenistan and Iran, which also border the Caspian, have also been invited as observers, AFP reported. But the Turkmen Foreign Ministry said in a statement: "Turkmenistan, as a neutral state, is not taking part and does not intend to take part in future in any military exercises on the Caspian, either as a participant or as an observer."

"Turkmenistan considers it pointless to hold large-scale military exercises on the Caspian Sea, in as much as Caspian states, with the exception of Russia, do not have large naval forces on the Caspian," the statement added.

The exercises have been seen as an attempt by Russia to show its military strength and ability to protect its interests at a time when the issue of how to divide up the oil and gas riches of the Caspian Sea remains unresolved.

Azerbaijan, Kazakhstan and Russia want to split the sea according to the length of the nation's shorelines.

But this would leave Iran with the smallest share of around 13 percent of the Caspian. Tehran is pushing for the sea to be split five ways into equal portions of 20 percent each.

Turkmenistan's position remains largely unclear although the Central Asian state often sides with Iran in the dispute and is keen to thwart any attempt by Russia to restore its Soviet-era control in the region.

Ashkhabad's military participation in the exercises had been considered unlikely as the former Soviet republic has avoided involvement in any military groupings since it gained independence and has pursued an isolationist path.