Nato ships have begun anti-piracy operations off Somalia, the alliance said.
Nato Secretary-General Jaap de Hoop Scheffer said a Nato ship was escorting a UN World Food Programme vessel due to dock in Mogadishu yesterday. Another had escorted a ship talking supplies to Burundian peacekeepers in the country.
"The operation is moving well," Mr de Hoop Scheffer told a news briefing.
Somali pirates have been causing havoc in one of the world's busiest shipping areas connecting Europe to Asia and the Middle East, taking millions in ransoms, hiking insurance costs, and threatening humanitarian supplies.
Responding to a UN request, the 26 Nato allies authorised ships from a force of two destroyers, four frigates and one auxiliary ship from six Nato states to join an international naval effort against the pirates.
In an interview with Reuters, a regional maritime official said international naval patrols may deter piracy off Somalia, but the kingpins remain untroubled enjoying the fruits of this year's rash of hijackings in cities around the world.
Andrew Mwangura, whose East African Seafarers' Association monitors piracy, said that while the patrols should calm the situation, the problem needed to be dealt with at its roots.
Meanwhile, the commander of a Nato task force said he still does not know what the rules are for taking on the high-seas bandits.
US Admiral Mark Fitzgerald said while he was aware of where the pirates were operating, there was little he could do militarily to stop them and that guidelines on how to take them on - including whether to shoot - were still in the works.
Six Nato members have contributed ships, including destroyers and frigates, to a special anti-piracy task force following a request from the UN.
The Nato group passed through the Suez Canal during the middle of the month on its way to the Horn of Africa, where piracy has surged this year, with more than 30 ships seized and ransoms estimated at €14 to €24 million have been paid to free hostages.
There are already naval assets from Britain, the US and Russia in the region, but the area is so vast - more than 2.5 million square miles - that it is almost impossible for the pirates to be stopped unless they are caught red-handed.
"From a military standpoint, we certainly are limited by what we can do," said Mr Fitzgerald. "How do you prove a guy's a pirate before he actually attacks a ship?
"We have a problem from the military side at sea because we can't be omnipresent in the space, and the pirates operate at an advantage because... they don't announce they're a pirate until they attack a ship."