Spy claims strain Israel-Turkey ties Relations deteriorated in May 2010 when Israeli commandos boarded protest ships seeking to break the Israeli naval blockade of Gaza. Persistently strained relations between Israel and Turkey have not been helped by a report that last year Turkey revealed to Iran the identities of up to 10 Iranians who had spied for Israel. The Israeli government would not comment on the report on Thursday, but Danny Yatom, a former head of Mossad, Israel's intelligence agency, told Israel Radio: "Assuming that this is true, this was an extraordinarily malicious thing to do." A column by David Ignatius published on Wednesday on The Washington Post's website reported that early last year the Turkish government made the disclosures about Iranians who had been meeting Israeli intelligence officers on Turkish soil. Ignatius said "knowledgeable sources" called the episode a "significant" loss of intelligence and "an effort to slap at the Israelis," and that the betrayal had marred a 50-year intelligence alliance between Turkey and Israel. Turkish Foreign Minister Ahmet Davutoglu said in televised remarks on Thursday that the allegations were "without any foundation." Turkey, which shares borders with Iran, Iraq and Syria, once served as "a convenient place for Israel to work to reach people from hostile countries," said Mr Yatom, who lost his job as Mossad chief after a botched attempt to assassinate Hamas leader Khalid Meshal in Jordan in 1997. But while there had been "outstanding" co-operation in earlier years between Israel and Turkey, Israel now is "not open with the Turks, as we were in the past," he said. Turkey once ranked as Israel's closest ally in the Muslim world, taking part in joint exercises with the Israeli and US navies and allowing Israeli jet pilots to train in Turkey's relatively vast airspace. But relations began to sour over Israel's deadly three-week Operation Cast Lead offensive in the Gaza Strip in the northern winter of 2008-9. The partnership weakened further in May 2010, when Israeli commandos met resistance when boarding protest ships seeking to break the Israeli naval blockade of Gaza, and eight Turks and an American of Turkish descent were killed. Turkey sharply downgraded ties with Israel in September 2011, expelling the Israeli ambassador after Israel refused to apologise for the deaths. In December 2011, Israel cancelled a $US141 million contract to supply Turkey with an aerial intelligence system. An Israeli official said at the time that Turkey's shifting allegiances led Israel to fear that the delicate technology could end up in the hands of hostile governments. With Syria's descent into a civil war, the United States urged Israel and Turkey to restore co-operation, brokering a reconciliation agreement in March. As part of the deal, Israeli Prime Minister Benjamin Netanyahu officially apologised for "operational mistakes" that led to the deaths on the protest ship and committed to a further easing of restrictions on the Gaza Strip. The sides were then meant to agree on compensation and normalise ties. But contacts were frozen in June when Turkey was convulsed by weeks of protests.