Turkey to pressure Georgia to release tanker captain

* Minister to request captain's release, says govt source

* Turkey says Georgia violated maritime law

By Zerin Elci

CAIRO, Sept 2 (Reuters) - Ankara will pressure Tbilisi to overturn a Georgian court decision to imprison a Turkish tanker captain for trying to deliver fuel to rebel Abkhazia, violating an economic blockade, a government source said on Wednesday.

Foreign Minister Ahmet Davutoglu is expected to visit Tbilisi to ask Georgia to overturn the decision to jail the captain for 24 years after his ship was seized in the Black Sea by the Georgian Coast Guard.

Georgian authorities say the ship was seized in Georgian waters, but the tanker operator says the vessel was seized in international waters at gunpoint. A Russian coast guard official was quoted on Tuesday calling the seizure piracy.

"We think the Georgians violated international maritime law regarding both the letter and the spirit of the law," said Foreign Minister spokesman Burak Ozugergin.

"Davutoglu has a planned trip to Georgia in the coming days (to ask for the court decision to be overturned)," said a government official speaking on condition of anonymity. Davutoglu was on a Middle East tour in Egypt on Wednesday. No date was given for a trip to Georgia.