(Adds quote from chairman, background)

CAIRO, May 25 (Reuters) - EgyptAir will contract two foreign companies, one French and one Italian, to help search for the black boxes of its plane that crashed in the Mediterranean, the airline's chairman said on Wednesday

EgyptAir flight 804 crashed on Thursday with 66 people on board including 30 Egyptians and 15 from France in an area of the Mediterranean where the waters can be 3,000 metres deep.

"We have contracted a French and an Italian company to conduct deep sea searching in the Mediterranean, 3,000 metres deep," EgyptAir chairman Safwat Moslem told a news conference.

The plane and its black box recorders, which could explain what brought down the Paris-to-Cairo flight as it entered Egyptian air space, have not been located.

Investigators are looking for clues in the debris and human remains recovered so far from the Mediterranean Sea.

(Reporting by Ahmed Aboulenein and Ahmed Tolba; Editing by Dominic Evans) ((ahmed.aboulenein@thomsonreuters.com; +20 2 2394 8097; Reuters Messaging: ahmed.aboulenein.thomsonreuters.com@reuters.net))