TEL AVIV ø Israel's national air carrier, El Al, has canceled all flights to and from Turkey due to an escalating dispute over security.

The move on Thursday was ordered by the Israel Security Agency that had determined that Turkey's security arrangements were unsafe for Israeli passengers. Officials said the next step would be to cancel flights to Israel by the state-owned Turkish Airways.

For years, Turkey has allowed Israel to deploy its security agents and special detection equipment at Istanbul airport. Over the last few months, Turkish officials have warned that this arrangement would not be to continued, Middle East Newsline reported.

In early June, Turkish authorities refused to renew the work permits of dozens of Israeli security officers who work in Istanbul airport. About 350,000 Israelis per year ø the lion's share being tourists ø travel to Turkey.

"We have both a security and a diplomatic crisis here," an Israeli official said. "It is obvious that the [Turkish] political leadership refused to defuse the situation. I think the Foreign Ministry understands this."

Officials said they were concerned that the security crisis was a result of a declining political relationship between Ankara and Jerusalem. They cited Turkey's severe criticism of Israel's war against Palestinian insurgents and Prime Minister Recep Erdogan's warning that Israel's policy could lead to an upsurge in anti-Semitism.

Hours before El Al suspended its flights to and from Istanbul, Turkey was rocked by a series of bombings in major cities in which four people were killed. Israeli officials said the suspension of the El Al flights was not connected to the bombings.