Italy has asked the Somali prime minister for help in freeing an Italian ship hijacked by Somali pirates in December.

During a meeting in Rome, Prime Minister Mario Monti asked his Somali counterpart, Abdiweli Mohamed Ali, for help in freeing the Enrico Levoli, which had 18 crew members on board.

The tanker was hijacked on 27 December off the coast of Oman while carrying 15,750 tons of caustic soda from the United Arab Emirates to the Mediterranean Sea.

The same ship was attacked by pirates in 2006.

Ali assured Monti of "his personal engagement in aiding the liberation of the Italian ship and its crew, underscoring his government's strong commitment to preventing the scourge of piracy".

Three hijacked Italian vessels were freed by Somali pirates in November and December, two of them reportedly following ransom payments.

The Savina Caylyn, an oil tanker with five Italians and 17 Indians on board, was freed on December 21 after more than 10 months in captivity.

In January, a report by the British thinktank Chatham House showed that piracy off the coast of Somalia was helping to drive economic growth in parts of the country, with ransoms paying for developments.