PARIS, April 15 (Reuters) - Six Somali pirates who seized a French luxury yacht and held its 30 crew hostage for a week will be brought to France to face trial, a judge said on Tuesday.

French troops arrested the pirates in the Somali desert on Friday after they had handed over the hostages and fled with their ransom. Those arrested were just part of the pirate crew, and some of the ransom was recovered with them.

"The six men will be transferred to Paris tonight or Wednesday night," said the French judge, who spoke on condition of anonymity, adding that the men were being held by French troops in Djibouti and would be flown to France.

French officials said last week France had the right to try the pirates, believed to be Somali fishermen, but some experts have questioned the legality of such a trial.

The armed group attacked the yacht on April 4 some 850 km (530 miles) off the Somali coast. They then sailed the boat and its crew -- 22 of whom are French -- to Somalia.

The crew were flown back to Paris on Monday.

Somali President Abdullahi Yusuf had agreed to let French troops bring the pirates to France for trial, the judge said.

"These pirates are currently on a French boat and we are awaiting President Yusuf's confirmation before bringing them to France, where we want these pirates to be tried," Prime Minister Francois Fillon told parliament on Tuesday afternoon.

France has called for greater international cooperation to police the waters off lawless Somalia's coast, where piracy is a lucrative activity.

This case "marks the start of a reconquering of this zone by international law", Fillon told lawmakers.

The pirates will be held for questioning upon their arrival in France. A preliminary investigation was launched on Monday for "boat hijacking, kidnapping and confinement in an organised gang with ransom payment" which carries a maximum life sentence. (Reporting by Thierry Leveque; writing by Francois Murphy; Editing by Jon Boyle)

AlertNet news is provided by