A Royal Navy admiral took charge yesterday of the European Union’s first naval task force, assembled to protect international shipping in the waters off Somalia amid calls for a United Nations pirate court to be set up to try those apprehended at sea.

Six warships and three surveillance aircraft from eight countries will be co-ordinated by Rear Admiral Phillip Jones to patrol a million square kilometres of the Indian Ocean and Gulf of Aden, where heavily armed pirates have captured nearly 30 vessels and taken 300 hostages this year alone.

The captives include two Britons among the 25-strong crew that remains on board the Sirius Star, a fully-laden oil tanker seized by pirates on November 15.

Germany has led calls for a debate on a UN special pirate court for those caught by the European mission, given that the EU will not transfer prisoners to countries with the death penalty, potentially leaving it with pirates on its hands.

Underlining the urgency of the task, a Dutch vessel came under attack from small-arms fire and a rocket-propelled grenade at the weekend from pirates on two speed boats, the International Maritime Bureau piracy reporting centre said.

“The ship caught fire but the captain successfully took evasive action to prevent a hijack. The ship sustained damage but managed to continue its voyage,” said Noel Choong from the IMB.

The incident happened 450 nautical miles east of Dar es Salaam in Tanzania, showing that the pirates are venturing ever further from their bases in Somalia.

“Pirate attacks are spreading to a wider area down south from the Somalia coast. This is not a good sign. Pirates have become bolder and more dangerous. They are also firing automatic weapons and rockets indiscriminately,” Mr Choong added.

The first EU warships, including a British frigate, are due to arrive in the area on December 15 after formal agreement by foreign ministers at a meeting in Brussels yesterday. They will take over from four Nato vessels.

In addition to the EU vessels, about a dozen other warships from the US 5th Fleet based in Bahrain, as well as from India, Russia and Malaysia and other nations are patrolling in the area.

There were the first signs of disagreement over the scope of the EU mission when Germany indicated that it was not prepared actively to pursue and arrest pirates.In a leaked letter, Frank-Walter Steinmeier, the German Foreign Minister, and Franz Josef Jung, the Defence Minister, wrote that: “Arresting people suspected of piracy is not the primary objective of the [German] operation.”

Arrested pirates could pose a legal problem for the navy that apprehends them, because the EU terms of engagement state that they should be handed for trial to the country where the attacked vessel is registered. This will not always be possible, given the international nature of shipping registration and the block on EU prisoners being sent to countries with capital punishment.

Germany said that the EU was in negotiation to hand captured pirates to Kenya for trial but called for debate on whether the United Nations should set up a new court for pirate trials. "The EU is reviewing agreements whereby suspects could be taken by third countries that are willing and in a position to launch criminal proceedings," said Mr Steinmeier.

"Moreover we are in favour of reviewing whether the United Nations could use existing international courts or found a new one to conduct such criminal proceedings."

Faced with such a huge area to patrol, the European Community Shipowners' Association has asked the EU to concentrate its efforts on protecting boats that it deems vulnerable, either because they are too slow or too low in the water, allowing easy boarding.

There were reports at the weekend that Somali pirates holding a Ukrainian cargo ship carrying 33 tanks had threatened to pull out of a deal for its release after accusing the owners of stalling on a ransom payment.

Somali sources have said that a ransom of $3.5 million (£2.4 million) has been agreed for the ship, carrying battle tanks, rocket launchers and ammunition, which was seized two months ago.

The EU has conducted 20 peacekeeping operations around the world but this will be its first naval mission. It will not extend to land operations against pirate bases, which some leading figures believe is the only way to stamp out the practice.

General John Craddock, Nato’s top commander, last week said: “You do not stop piracy on the seas. You stop piracy on the land.”

Seyoum Mesfin, the Foreign Minister of Somalia’s neighbour Ethiopia, added: “The pirates are not fish who just sprang up out of the sea. They came out of Somalia. It is far-fetched to try to clamp down on piracy without first having put the situation in mainland Somalia under control."

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