A French military aircraft spotted the Ponant on Saturday
France says it has made contact with Somali pirates who seized a luxury French yacht and its crew of about 30.
Foreign Minister Bernard Kouchner said everything would be done to avoid bloodshed and did not rule out paying a ransom to free the crew.
The Ponant was boarded by pirates in the Gulf of Aden on Friday and is now reported to be anchored off Somalia. There are no passengers aboard.
Somali coastal waters are among the world's most hazardous.
More than 25 ships were seized by pirates there in 2007.
"We've made contact and the matter could last a long time," Mr Kouchner told France Inter radio.
French Defence Minister Herve Morin earlier said a military operation to free the crew would only be attempted if their safety could be guaranteed.
The French coastal frigate, Le Commandant Bouan, has been diverted from Nato duties to track the yacht and a French military plane based in Djibouti has overflown the vessel.
A Canadian helicopter on the HMCS Charlottetown also was taking part in the operation, the Associated Press (AP) said.
Officials in the semi-autonomous region of Puntland, in north-eastern Somalia, said the Ponant had anchored nearby.
The French company that owns the vessel, CMA-CGM, said on Sunday that its crew were thought to be unharmed.
The 850-tonne three-masted yacht was sailing back to the Mediterranean from the Seychelles when it was seized with its crew of 22 French nationals and 10 others - thought to be Ukrainians and Koreans.
The hijacked yacht can take up to 64 passengers and is designed for cruising in some style.
It has four decks, two restaurants and also indoor and outdoor luxury lounges.
The threat from pirates prompted France to order its navy, in November last year, to escort two ships carrying food aid to Somalia.
In November 2005, pirates attempted to board a cruise ship carrying 600 passengers off the Somali coast.
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