Turkish Prime Minister Recep Tayyip Erdogan said on Thursday Israel could not do whatever it wanted in the eastern Mediterranean and that Turkish warships could be there at any moment.
Erdogan's comments, made during a visit to Tunisia as part of a tour of Arab countries, were the latest in a war of words between the two regional powers, whose relations have deteriorated since Israel killed nine Turks aboard an aid ship headed for Gaza last year.
"Israel cannot do whatever it wants in the eastern Mediterranean. They will see what our decisions will be on this subject. Our navy attack ships can be there at any moment," Erdogan told a news conference shortly after arriving in Tunis.
Turkey downgraded diplomatic ties with Israel and halted defense-related trade after the Jewish state confirmed last week it would not apologise for the raid on the Mavi Marmara ship which had attempted to break Israel's blockade on Gaza.
Turkey and Israel had tried to mend fences before the publication two weeks ago of a UN report that deemed the blockade of the Hamas-ruled Gaza Strip a legal means to stem the flow of arms to Palestinians but also said Israel had used unreasonable force.
Ankara said it was prepared to escort any future Gaza-bound ship with naval ships.
Israel has said it will maintain the blockade and that it wants to ease tensions with its former ally.
But in an interview last week with Al Jazeera television, excerpts of which were released by Turkish state media, Erdogan said he saw the Israeli storming of the ship in May, 2010 as "grounds for war" but that Turkey had acted "with patience".
The prospect of a showdown at sea with Turkey, a NATO power and, like Israel, an ally of the United States, rattled Israelis already on edge over political upheaval in the Arab world and Iran's nuclear program. Washington has appealed for restraint.
Erdogan, seeking to expand Turkey's regional influence, is on a tour of Egypt, Tunisia and Libya, where he has so far received an enthusiastic welcome. His criticism of Israeli has helped win him great popularity in Arab countries.