The Sirius Star has 25 crew - who are said to be unharmed
The owners of a Saudi Arabian oil tanker hijacked by Somali pirates are negotiating a possible ransom, the Saudi foreign minister has said.
The Sirius Star is the biggest tanker ever hijacked, carrying a cargo of two million barrels of Saudi oil - worth more than $100m (£67m).
Saudi's Prince Saud al-Faisal did not confirm whether a ransom was likely to be agreed, but said talks had begun.
Meanwhile, the Indian navy says it has sunk a suspected pirate "mother ship".
INS Tabar sank what was believed to be a Somali pirate "mother ship" after it failed to stop for investigation and instead opened fire in the Gulf of Aden, an Indian navy statement said.
Mark Dolan, friend of hostage Peter French: 'He will be most angry and frustrated'
The captive crew on the Sirius Star include two British citizens, two Poles, one Croatian, one Saudi national and 19 Filipinos.
The Britons include Peter French, the chief engineer on board the vessel.
The other is Second Officer James Grady, from Strathclyde. Their families released a statement on Wednesday saying they hoped they would be home safely very soon.
There has been a surge in piracy incidents off the coast of Somalia during 2008. On Tuesday, a cargo ship and a fishing vessel became the latest to join more than 90 vessels attacked by the pirates this year.
The pirates who seized the MV Sirius Star and its 25 crew on Saturday are a sophisticated group with contacts in Dubai and neighbouring countries, says the BBC Somali Service's Yusuf Garaad.
Much of their ransom money from previous hijackings has been used to buy new boats and weapons as well as develop a network across the Horn of Africa, he adds.
'Scourge' of seas
Asked whether a ransom was being negotiated, the Saudi foreign minister said the decision rested with the owners of the tanker.
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