Russia says the Syria-bound plane intercepted by Turkey amid reports it was carrying cargo which could aid government war efforts was transporting a legal shipment of radar equipment. "There were no weapons on the plane," said Foreign Minister Sergei Lavrov.
His comments followed heated exchanges between Turkey and Syria over the exact nature of the items confiscated.
Turkey's PM earlier said Russian-made defence equipment was found on board - a claim Syria dismissed as a lie.
Damascus has challenged the Turks to put the confiscated items on public view, something Ankara has declined to do so far.
On the border tensions continued, with Turkey reportedly scrambling fighter jets after an air attack on a Syrian frontier town by Syrian government forces.
And in Syria itself, activists said rebel fighters had seized a government air defence base near the embattled north-western city of Aleppo.
