JERUSALEM, Aug 2 (Dan Williams/Reuters) - Israel's Defense Minister Ehud Barak has voiced concern that once-stalwart ally Turkey could share Israeli intelligence secrets with Iran, revealing a deep distrust as Ankara's regional interests shift.

The leaked private comments by Barak cast doubt on how much Israel is willing or able to reconcile with Turks outraged at its killing of nine of their compatriots aboard a pro-Palestinian aid ship on May 31.

Until relations soured, Turkey was the Jewish state's closest Muslim ally in a friendship largely based on military cooperation and intelligence sharing.

In a closed-door briefing to Israeli community leaders at a kibbutz outside Jerusalem on July 25, Barak still described Turkey as a friend and major strategic ally.

But he called Hakan Fidan, the new head of its National Intelligence Organisation, a friend of Iran.

There are quite a few secrets of ours (entrusted to Turkey) and the thought that they could become open to the Iranians over the next several months, let's say, is quite disturbing, Israel's Army Radio quoted him as saying in the speech. The Defence Ministry declined comment, but a person who attended the kibbutz event told Reuters on Monday the Army Radio report was accurate, and that Barak had been speaking in the context of past Israeli-Turkish intelligence cooperation.


MEDIATOR

Appointed in May, Fidan was previously a foreign policy adviser to Prime Minister Tayyip Erdogan, whose AK Party has roots in political Islam and has often censured Israel. Turkish sources say Fidan has also helped to mediate between the West and Iran over Tehran's disputed nuclear programme.

Israel has hinted at last-ditch military strikes to deny the Iranians the means to make a nuclear bomb -- a threat boosted by its 2007 air raid on an alleged atomic reactor in Syria, during which Israeli warplanes briefly flew over Turkish territory.

The Erdogan government was angered by that incursion and has pointed to Israel's own assumed nuclear arsenal. Such positions have helped NATO-member Turkey to rally Arabs and Muslims as a dominant Middle East force. Ankara has not commented publicly on the state of its intelligence ties with Israel. But some Turkish commentators have looked askance at media reports of Israeli collaboration with Kurds in northern Iraq, given their suspected ties to Turkey's separatist Kurdish guerrilla group PKK.

By contrast, Israel's Mossad spy agency was widely reputed to have helped Turkey to capture PKK leader Abdullah Ocalan in 1999, though then-Mossad chief Efraim Halevy denied involvement.

There has also been ridicule in Turkey of an Israeli inquiry into the interception of the aid ship Mavi Marmara outside blockaded Gaza, which faulted military intelligence for not anticipating passengers' resistance to the naval boarding party.

Marines shot dead nine Turks in the ensuing brawls, an action Israel has justified as self-defense. Turkey, which withdrew its ambassador and suspended joint military exercises with Israel in protest at the bloodshed, has demanded an apology and a wider international investigation. (Editing by David Stamp)