"I can say now that in Damascus a series of responses is being examined at the highest political and military levels. The results will not take long in coming," Shara told La Repubblica during a visit to Rome.

Syria said on Thursday that its air defences opened fire on Israeli warplanes which had violated Syrian airspace at dawn the same day, ratcheting up the tension between the neighbouring foes.

Israel declined to comment.

Shara also criticised the vagueness of plans for a US-sponsored international Middle East peace summit set to take place in the autumn.

"At the present time, the programme is vague: parameters for an agreement, a list of the countries invited and even the date are missing," he told the paper.

"The risk is that the United States will reduce the conference to a photo opportunity to detract attention away from Iraq."