Israel has not commented on a report that Jordan has opened two corridors of its airspace for Israeli unmanned air systems being used to monitor the security situation in Syria. The claim first appeared in French newspaper Le Figaro.

An unnamed source told the publication that Jordan decided to open the airspace following US President Barack Obama's visit to the region last month. According to its report, such permission means that Israeli assets will not have to fly over southern Lebanon en route to monitoring Syria.

Security co-operation between Israel and Jordan has tightened in recent years.

As previously reported by Flightglobal, the alleged use of a chemical weapon during the internal war in Syria has put the Israeli air force on its highest level of alert, with a "massive array" of sensors directed to the suspected areas.

According to reports from Syria, at least one chemical weapon was used a few weeks ago in clashes between the nation's army and rebel forces. The USA has said that it was evaluating allegations of chemical weapons use in Syria, but dismissed charges that the opposition had used such weapons during the two-year-old conflict.

The Syrian government and rebels both accuse each other of having launched a deadly chemical attack near the northern city of Aleppo.

Israel has been following the movement of parts of Syria's chemical weapons arsenal in recent months, with its air force having said that any sign of an intention to use such systems against Israel will be met with a "fierce reaction".

Syria's army has a large stockpile of weapons of mass destruction, and Israeli intelligence sources have previously claimed that some stocks have been put in the warheads of Scud-D surface-to-surface ballistic missiles.

Source: Flight International