Three days before a UN report on last year's deadly flotilla raid is due, Israeli and Turkish officials were engaged in feverish behind-the-scenes diplomacy in an effort to mend the bilateral ties that ruptured after the death of nine passengers aboard a Turkish ship.

The activists were killed by Israeli naval commandos who encountered violent resistance when attempting to keep the vessel from breaching Israel's blockade of the Gaza Strip.

Open gallery view The Mavi Marmara, aboard which Israel's deadly raid on a Gaza-bound flotilla resulted in the deaths of 9 Turkish activists May 22, 2010 Credit: AP

A meeting is scheduled for Tuesday in New York between Deputy Prime Minister Moshe Ya'alon and senior Turkish officials. A government source in Jerusalem said the United States has been exerting heavy pressure on both sides to work out their differences by the time the report comes out Thursday.

If a compromise is not reached soon, the UN report will be released as is, and bilateral ties will likely be frozen for a long period, the source said. If a compromise is reached, the report will be reworded and toned down.

"We are at a critical stage," the source said. "If things aren't worked out, the report will be released and everybody loses."

The UN committee reviewing the events of May 31, 2010, has sent a draft of its report to both Israel and Turkey.

According to a senior Israeli diplomatic source who read the draft, the committee concluded that the blockade of Gaza was legal, but that the naval commandos who seized the Mavi Marmara had used undue force.

Turkey, meanwhile, is concerned about the committee's apparent criticism regarding Ankara's role in the flotilla, particularly its ties with the group that organized it, IHH, which has links to Hamas.

Turkey has asked Israel to agree to have the report toned down as part of a deal meant to reconcile the two countries and bring the Turkish ambassador back to Tel Aviv.

The heart of the dispute remains Turkey's demand that Israel apologize for its role in the events.

"Diplomats are working like linguists to find a word that will sound like an apology in Turkish, but won't sound like an apology in Hebrew," the Turkish newspaper Hurriyet reported Monday.