TURKEY has raised the prospect of a naval confrontation with Israel by announcing it will deploy warships to protect humanitarian convoys attempting to breach the maritime blockade of Gaza.

Prime Minister Recep Tayyip Erdogan defended the move as a necessary response after Israel refused to apologise for the deaths of nine Turks killed during an operation to intercept a Gaza-bound aid flotilla last year.

The threat is the most dangerous escalation yet in a rapidly deteriorating diplomatic row between the former allies that has already seen Turkey expel Israel's ambassador and suspend all military ties.

Israel described the latest development as ''grave and serious''.

Israeli Minister of Foreign Affairs Avigdor Lieberman is expected to announce retaliatory action this weekend. The Israeli press reported he was considering meeting and possibly even financing Turkey's Kurdish rebel movement, a move that would incense Mr Erdogan's government.