JERUSALEM Israel will keep blockading Gaza in the face of Turkey's unprecedented naval challenge and is prepared for escalation though it wants to ease tensions with its former ally, officials said on Friday.
Deepening a crisis over Israel's killing last year of nine Turkish citizens aboard an aid flotilla that tried to reach the Palestinian enclave, Turkey vowed on Thursday to assign warships to escort such convoys in the future.
The prospect of a showdown at sea with Turkey, a NATO power and fellow U.S. strategic partner in the region, rattled Israelis already on edge over Arab world political upheaval and Iran's nuclear program.
Breaking an almost 24-hour-long silence on the warships comments, Prime Minister Benjamin Netanyahu's office said Israeli policy "was and remains the prevention of deterioration in our ties with Turkey and easing the tensions between the countries."
"The prime minister and cabinet discussed the various theoretical possibilities should escalation occur," it said in a statement. "But a decision on such will be made only if and when required."
Confrontation did not appear imminent after the IHH, a Turkish Islamist charity that owned the Mavi Marmara cruise ship stormed by Israeli marines on May 31, 2010, said in Istanbul it had no plan "for now" to mount another Gaza mission.
But Turkish Prime Minister Tayyip Erdogan also pledged to boost naval patrols around eastern Mediterranean gas fields being developed by Israel, a potential blow to the Netanyahu government's quest for energy independence.
The Obama administration appealed for restraint.
"We are quite concerned ... We are urging both sides to refrain from rhetoric or actions that could be provocative, that could contribute to tensions," State Department spokeswoman Victoria Nuland told reporters in Washington.
"Obviously, we would like to see both sides cool it and get back to a place where they can have a productive relationship."
Turkey and Israel had tried to mend fences before a U.N. report last week that deemed the blockade a legal means to stem the flow of arms to Gaza's governing Hamas and other Palestinian militants. Israel formally declared it during a 2008-2009 war with Hamas.
Turkey argues that the naval closure amounts to illegal collective punishment of Gaza's impoverished 1.5 million Palestinians and made lifting it a condition for reconciliation.
"There is no intent to review the blockade as long as Hamas amasses missiles. This is a measure consistent with international law," said Yigal Palmor, spokesman for Israel's Foreign Ministry.
The U.N. inquiry also called Israeli marines' gunfire in brawls aboard the Mavi Marmara "excessive and unreasonable" and the deaths caused "unacceptable." Israel voiced regret but rejected Ankara's demand for a formal apology and compensation.
While Turkey's navy outclasses Israel's, the latter could make use of its advanced air force in any coastal face-off. Yet analysts see them coming to blows as unlikely.
"The things Turkish Prime Minister Erdogan said are harsh and serious, but I don't think it would be right to get into any verbal saber-rattling with him," Netanyahu deputy Dan Meridor told Israel's Army Radio. "Our silence is the best response. I hope this phenomenon will pass."
Erdogan's comments about the eastern Mediterranean also drew a warning from the European Union not to threaten Cyprus, an EU member pursuing joint offshore gas drilling with Israel.
Non-EU-member Turkey is the only country that recognizes a separate Turkish-run state in Cyprus's northern third, which it invaded in 1974 in response to a Greek-inspired coup.
"You know that Israel has begun to declare that it has the right to act in exclusive economic areas in the Mediterranean," Erdogan said in his remarks on Thursday to Al Jazeera, which were translated into Arabic.
"You will see that it will not be the owner of this right, because Turkey, as the guarantor of the Turkish Republic of Northern Cyprus ... will be decisive and holding fast to the right to monitor international waters in the east Mediterranean."
EU spokeswoman Maja Kocijancic said: "The EU urges Turkey to refrain from any kinds of threats, sources of friction that could negatively affect good neighborly relations and the peaceful settlement of border disputes."
The Turkish-Israeli row is unlikely to embroil NATO, which operates on the basis of unanimous decisions, an official of the Western alliance said in Brussels.
"It's literally impossible for NATO to take any action that's not agreed by all 28 allies," the official said.
(Writing by Dan Williams; Additional reporting by Ari Rabinovitch in Jerusalem, Seltem Iyigunl and Ibon Villelabeitia in Istanbul, David Brunnstrom in Brussels and Arshad Mohammed in Washington)