According to the title, Russia has already made such claims since the missile strike on Syria on April 14. Sergey Rudskoy, the Chief of the Operational Directorate-General of Russia's Armed Forces was the first who claimed about such necessity. On April 16, Sergey Lavrov, the Foreign Minister of Russia also made such claim. He repeated it on April 20 for RIA News, claiming that Russia 'has no moral obligations' after the missile strike on Syria launched by the US and allies.
Also, on April 20, Russia's President Vladimir Putin held a meeting with the heads of the General Staff and Defense Ministry during which they discussed 'some aspects of the situation in Syria, according to the official version. However, no details were reported.
The sources closed to the military leadership reported that the issue of the handover of the missile systems to the Syrian army is almost decided. It is also noted that S-300 will be passed to Syria within the provision of the military and technical aid as Bashar Al-Assad's regime does not possess funds for the purchase. Also, Russia does not plan to draw a credit. It is supposed that the S-300 missile systems used by Russian army will be passed to Syria.
Russia's Defense Ministry has not published any official comments on this issue yet.
The issue of the handover of the Russian S-300 missile systems was raised by Syria in 2010. However, the concluded contract was canceled due to the position of Israel concerned about its airspace security. This time, it is supposed that the response can be even more negative down to the strikes on the supposed locations of the missile systems.