Syrian President Bashar Assad says he regrets the shooting down of a Turkish jet by his forces, and he will not allow tensions between the two neighbours to turn into an "armed conflict," a Turkish newspaper reported Tuesday.

Syria downed the RF-4E warplane on June 22, after it flew very low inside its airspace, according to Damascus. Turkey says the jet was hit in international airspace after it briefly strayed into Syria.

Assad offered no apology for the downing of the plane during an interview with Cumhuriyet in Damascus on Sunday, insisting that it was shot down over Syria, and his forces acted in self-defence.

He said that the plane was flying in a corridor inside Syrian airspace that had been used by Israeli planes in 2007, when they bombed a building under construction in northern Syria.

The UN nuclear agency has said that the building was a nearly finished reactor, meant to produce plutonium, which can be used to arm nuclear warheads.

"The plane was using the same corridor used by Israeli planes three times in the past," Assad told Cumhuriyet. "Soldiers shot it down since we did not see it on our radars and we were not informed about it."

Assad said: "I say 100 per cent, I wish we did not shoot it down."

Syria in 'state of war'

Turkey responded by deploying anti-aircraft missiles on the Syrian border, and has scrambled its jets several times after it said its border was approached by Syrian helicopters. A search for the wreckage of the plane and its two missing pilots is still underway in Syrian waters.

Assad said Syria had no intention of fuelling tensions along its border with NATO-member Turkey.

'We are in a state of war, so every unidentified plane is an enemy plane'—Syrian President Bashar Assad

"We will not allow it to turn into an armed conflict that would harm both countries," he said. "We did not build up our forces on the Turkish border and we will not."

He said Syria "would have apologized" for the shooting if the plane had not been shot down in Syrian airspace. He said the rise of tensions could have been prevented if channels of communication between the two militaries remained open.

"We are in a state of war, so every unidentified plane is an enemy plane," the paper quoted Assad as saying. "Let me state it again: we did not have the slightest idea about its identity when we shot it down."

Turkey, however, has insisted that the plane's electronic signals, which indicate if an aircraft is friend or foe, were activated during the entire flight and that Turkey even intercepted radio conversations in which Syrian forces referred to the plane.

Hurriyet newspaper, citing intelligence sources, said early last week that Syrian forces referred to the plane using the Turkish word for "neighbour" — "komsu" — in an intercepted radio conversation.

Turkey also insisted that the plane was not spying on Syria but just testing Turkey's radar capabilities.