The Danish government is calling for more legal clarity after one of its warships was prevented from arresting a boatload of suspected pirates off Somalia.
Personnel from the warship Absalon made contact with a boat in the Gulf of Aden, but could make no arrests as no offence had been committed.
However, after keeping the vessel under surveillance, the crew said they were sure it was the same group that tried to hijack an American cruise liner last Sunday.
In October, NATO sent four warships to patrol off the coast of Somalia, to protect convoys of UN humanitarian aid destined for famine-hit areas in the region.
Denmark has been in charge of a seperate multinational naval task force in the Northern Indian Ocean since September.
Their mandate has just been extended until April 2009.
It is reported up to eight armed pirates tried to board the Nautica, which carries 400 passengers and 200 crew, but they were repulsed by a helicopter sent from the task force.
On Tuesday, in what is said to be the most co-ordinated attack to date, an Italian warship saw off a dozen pirate boats circling a convoy of five tankers in the Gulf of Aden.