MOSCOW, April 27 (RIA Novosti) - Admiralty Shipyards in St. Petersburg will build six Kilo class diesel-electric submarines for delivery to Vietnam, the Russian business daily Kommersant said on Monday.

The paper quoted company general director Vladimir Aleksandrov as saying that Russia's state arms exporter Rosoboronexport would soon sign a contract with a foreign state, and that Admiralty Shipyards had been chosen to fulfill this contract.

Sources in Rosoboronexport later confirmed that Russia and Vietnam had been negotiating a $1.8 billion deal on the delivery of six Kilo-class submarines to the Vietnamese navy for about a year.

Admiralty Shipyards is currently building two Kilo class submarines for Algeria to be delivered in 2009 and 2010.

Kilo class submarines, nicknamed "Black Holes" for their ability to avoid detection, are considered to be among the quietest diesel-electric submarines in the world.

The submarine is designed for anti-submarine warfare and anti-surface-ship warfare, and also for general reconnaissance and patrol missions.

The vessel has a displacement of 2,300 tons, a maximum depth of 350 meters (1,200 feet), a range of 6,000 miles, and a crew of 57. It is equipped with six 533-mm torpedo tubes.

As of November 2006, 16 vessels were believed to be in active service with the Russian Navy and eight submarines were thought to be in reserve. Another 29 vessels have been exported to China, India, Iran, Poland, Romania and Algeria.