JERUSALEM, July 24 (Reuters) - Israel's Foreign Minister Avigdor Lieberman said on Sunday he would not quit the coalition government if it decides to apologise to Turkey for killing nine Turks aboard a pro-Palestinian activist ship last year.

Lieberman, Prime Minister Benjamin Netanyahu's most powerful and hawkish partner, has scorned meeting Ankara's demand that Israel atone for storming the Mavi Marmara as it tried to breach the blockade on the Gaza Strip at the head of an aid flotilla.

But after Israeli officials said Netanyahu might relent after long balking at an apology, Lieberman denied having any plan to resign or withdraw his party in protest.

"Whether or not there is agreement in the government about this matter, this government is strong," he told reporters. "No one is looking for excuses and reasons to leave the government."

Israel's debate over apologising to Turkey has been spurred by its expectation that an imminent U.N. report on the high seas interception will largely vindicate its Gaza blockade strategy.

Turkey, which like Israel had a delegate on the U.N. inquiry panel led by former New Zealand prime minister Geoffrey Palmer, has yet to sign the report and Netanyahu envoys have been in bilateral talks with Ankara in the hope of bridging the rifts.

Israeli officials had given July 27 as the report's release date, but on Sunday said this had been postponed to Aug. 20 to allow for further fence-mending efforts. The Turkish embassy and local U.N. mission did not immediately return calls for comment.

Defence Minister Ehud Barak, a centre-leftist in the Israeli cabinet and proponent of accommodating the Turks, had earlier said he hoped the repeatedly deferred publication would again be pushed back "to provide more time to examine matters in-depth".

The Netanyahu government has so far offered only expressions of "regret" at the Mavi Marmara bloodshed and proposed setting up a "humanitarian fund" for those bereaved or injured.

INDEMNITY

At the time, his advisers said a formal apology and damages payments would be tantamount to Israel admitting culpability for its marines' lethal gunfire during fierce brawls aboard the Mavi Marmara. Both sides have described the fighting as self-defence.

But Israeli officials say legal reviews have since found that placating the Turks so that they endorse the Palmer report, even at the cost of an apology, would shore up naval personnel against pro-Palestinian lawsuits in international courts.

"Alongside preserving the State of Israel's honour and asserting its righteousness, we have a supreme interest in protecting officers, commanders and combatants from possible prosecution aboard," Barak told reporters.

Israel says the blockade prevents arms reaching Gaza's ruling Hamas Islamists, who are hostile to the Jewish state.

Yet Turkish Prime Minister Tayyip Erdogan, who has shown willingness to engage Hamas, on Saturday reiterated his view that the blockade is "illegal and inhuman" and insisted Israel must end it as another condition for rapprochement.

"He's not exactly making it easy for us to apologise," said one Netanyahu aide in response.

According to Israel's state-funded Channel One TV, Netanyahu and his inner council were drafting an elliptical statement of contrition that would acknowledge the Erdogan government's sensitivities while not explicitly shouldering blame.

There might be a precedent for that in Israel's hedged apology for its jets' unauthorised transiting of Turkish territory en route to a secretive bombing run in Syria in 2007.

"If indeed Israeli planes entered Turkish airspace, then there was no intention of undermining or questioning Turkish sovereignty, which we respect," then Prime Minister Ehud Olmert said in broadcast remarks to the Israeli cabinet.

Turkey, once a rare Muslim ally of the Jewish state, withdrew its ambassador to Israel after the Mavi Marmara seizure in May 2010, suspended defence cooperation and closed its airspace to Israeli military planes.