A top Israeli minister on Friday described as "grave and serious" a threat by Ankara to send warships to escort any aid vessels trying to reach the Gaza Strip in defiance of Israel's naval blockade.

Israel and Turkey have been locked in a bitter dispute since May 2010 when Israeli naval forces stormed the Freedom Flotilla, a convoy of six international aid ships trying to reach Gaza, killing nine Turkish nationals.

The crisis deepened over the past week, with Turkey expelling the Israeli ambassador and axing military ties and defence trade.

On Thursday night, Prime Minister Recep Tayyip Erdogan vowed that Turkish warships would escort any aid ships trying to reach the Palestinian enclave.

"These remarks are grave and serious," senior cabinet minister Dan Meridor told army radio, while indicating that Israel had "no wish to add to the polemic."

"It is better to stay quiet and wait -- we have no interest in aggravating the situation by replying to such (verbal) attacks," said Meridor, who is also minister of intelligence and atomic affairs.

Speaking to Al Jazeera television in Turkish, Erdogan said Ankara would dispatch warships to protect any Turkish aid ships seeking to reach Gaza in defiance of the Israeli blockade.

"Turkish warships will be tasked with protecting the Turkish boats bringing humanitarian aid to the Gaza Strip," he said in remarks which were translated into Arabic.

"From now on, we will no longer allow these boats to be the targets of attacks by Israel, like the one on the Freedom Flotilla, because then Israel will have to deal with an appropriate response," he warned.

A senior Israeli official, speaking to AFP on condition of anonymity, called Erdogan's remarks "a very grave provocation," although he said it was unlikely that he would actually make good on his threats.

"It is very difficult to imagine that Turkey would go so far as to take such action, given its commitments to NATO," he said.

Meridor also said that Ankara "would be violating international law" if it tried to break the naval blockade by force, which a UN report into the flotilla incident declared to be legal.

But Alon Liel, a former Israeli ambassador to Turkey and expert on the relationship between the two countries, said Erdogan's warnings should not be taken lightly.

"This warning should be taken more seriously than a hypothetical expression of support for any Gaza-bound flotilla, taking into account Turkish interests in the region," Liel told AFP.

"Such an action would involve additional complications with Cyprus and Greece," he said.

The most recent crisis between Israel and Turkey was sparked last week following the release of the long-awaited UN report into the flotilla incident.

The report's authors concluded that Israel's naval blockade was valid under international law and that its forces had the legal right to stop Gaza-bound ships in international waters, which deeply angered both Turkey and the Palestinians.

But it also said Israeli troops had used "excessive and unreasonable" force in stopping the boats, and described the loss of life as unacceptable.

Hours after the report was published, Ankara expelled the Israeli ambassador and suspended all military ties, while on Tuesday it also cut defence-related trade in protest over Israel's refusal to apologise.

Israel says its troops fired only in self-defence after they were attacked by activists on the deck of the Mavi Marmara, the Turkish ferry leading the flotilla, but Ankara has insisted on an apology for the bloodshed.

Israel has refused and the ensuing diplomatic row has strained their once-close relations to breaking point.