A European Union flotilla is deploying five days early to waters off the Horn of Africa, determined to combat piracy amid growing alarm over attacks on international shipping.

On Dec. 15, four EU warships and two maritime reconnaissance aircraft will replace the four-vessel NATO flotilla that has been conducting anti-piracy patrols off the Somali coast, EU foreign ministers announced Monday during their monthly meeting.

EU foreign policy chief Javier Solana called it "a very important mission ... in a place in the world that everybody's looking at because of the problems related to piracy."

The EU has conducted 20 peacekeeping operations so far, but this is its first naval endeavor. The task force — codenamed Operation Atalanta — will have the same duties as the NATO mission, including escorting ships carrying relief aid to Somalia, protecting merchant ships and deterring pirate attacks.

An initial EU force will start patrolling Tuesday in the Gulf of Aden. It will be increased shortly by another aircraft and one or two more ships, officials said.

Britain, France, Greece, Sweden, Spain, Belgium, and the Netherlands have agreed to contribute at least 10 warships and three reconnaissance aircraft to the one-year mission. The contingents will be rotated every three months, and at least four vessels will be on duty at all times.

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

The NATO force successfully delivered nearly 30,000 tons of humanitarian supplies to Somalia but was not been able to stem a surge in pirate attacks. Pirates attacked 32 vessels and hijacked 12 of them since the NATO operation began Oct. 24.

Cristina Gallach, spokeswoman for Solana, said the EU flotilla would operate under "robust rules of engagement" but declined to elaborate.

Under a U.N. Security Council mandate, the international fleet is not allowed to board seized ships or to free crews held hostage.

The EU task force will be commanded by British Vice Admiral Philip Jones from his headquarters near London. The vessels and their 1,200 crew members will be based at the Red Sea port of Djibouti and in Kenya.

"This operation under British command, I hope will begin to establish international order in seas that are vital to trade right around the world," said British Foreign Secretary David Miliband.

Somalia has been in chaos for nearly two decades, and the country's Western-backed transitional government has failed to assert any real control since it was formed in 2004.

About 50 cargo ships travel daily through the Gulf of Aden, a strategic waterway that links the Indian Ocean with the Suez Canal and the Mediterranean Sea.