Analyst: Turkish military moved to avoid losing parliamentary approval

Ankarali Jan, a Turkey analyst, told Middle East Eye that the operation in northern Syria was likely being carried out now because the original legislation allowing for such an intervention was about to expire.

"Parliamentary approval for an operation in this area was due to run out in early September," he explained. "And the government waited until parliament was suspended to begin sending in troops."

The original approval, which passed through parliament in September 2014, gave permission for the army to carry out "operations as necessary beyond Turkey's borders and to be sent to foreign countries for interventions and to the same ends for foreign armed forces to be allowed into Turkey".

Ankarali Jan said that it was "also a time of great chaos in the Turkish military, with purges and arrests of many of those accused of being accomplices to last month's coup attempt," though he added "that may also have opened the way for this operation - the Turkish military appears to have been standing firm against any large-scale Syrian operation up until now".

"The motives of the Turkish government are also mixed: revenge on IS for recent terror attacks will certainly be one motivation, though it has been well-documented in the Turkish press that local officials were happy to allow men and material destined for IS through the border. Preventing the Democratic Union Party (PYD), whose sister-party the Kurdistan Workers Party (PKK) is killing several Turkish soldiers a day in the country's southeast, from uniting the two parts of its Syrian territory has to be another motive."