ANKARA: The Turkish and Syrian navies conducted a joint search yesterday for Turkish airmen shot down by Syria over the Mediterranean, only a short distance from a Turkish province hosting thousands of rebels fighting President Bashar Al Assad.

Signals from both sides suggested neither wanted a military confrontation over Friday's shooting down of the jet near their borders.

However, the joint operation will clearly sit uneasily with both forces, given the bitter hostility between the two former allies over Assad's 16-month-old crackdown on opponents.

Iraq, which borders both countries, said the incident marked a serious escalation of the Syrian conflict and demonstrated its potential to infect other countries in the region.

"No country is immune from this spillover because of the composition of the societies, the extensions, the connections, the sectarian, ethnic dimensions," Iraqi Foreign Minister Hoshiyar Zebari said in Baghdad.

"This is not an excuse to do nothing about Syria, no. But there will be an impact."

Turkey has declared it will respond decisively.

"It is not possible to cover over a thing like this. Whatever is necessary will no doubt be done," Turkish President Abdullah Gul said, adding that Ankara had been in telephone contact with Syrian authorities.

The incident, whatever its causes, showcased Syria's Russian-supplied air defences - one of the many reasons Western powers are loathe to intervene to halt bloodshed in the country.

UN Secretary-General Ban Ki-moon urged Turkey and Syria to handle the matter with restraint, using diplomatic channels.

Turkey's Deputy Prime Minister Bulent Arinc said the downed jet was a reconnaissance aircraft. Turkish media had said it was an F-4 Phantom, a fighter also used for reconnaissance.

According to a Syrian military account, the Turkish plane was flying fast and low, just 1km off the Syrian coast when it was shot down. It had been tracked at first as an unidentified aircraft and its Turkish origin established subsequently.

"The navies of the two countries have established contact. Syrian naval vessels are participating along with the Turkish side in the search operation for the missing pilots," it said.

With the second biggest army in Nato, a force hardened by nearly 30 years of fighting Kurdish rebels, Turkey would be a formidable foe for a Syrian military already struggling to put down a popular uprising and an increasingly potent insurgency.

Foreign Minister Ahmet Davutoglu met Turkey's military commanders and intelligence chief to discuss the search for the pilots and Ankara's next steps.

Prime Minister Tayyip Erdogan was to hold a second security meeting with senior officials, less than 24 hours after he convened a crisis session on Friday evening.