However, defense analysts have questioned whether an S-300 system in Syrian, not Russian, hands could threaten Israel's air power in the region and prevent it from being able to conduct strikes against targets in Syria.
"This has pushed us to adopt adequate response measures directed at boosting the security of Russian troops" in Syria, Shoigu said in a televised statement.
Russian Deputy Foreign Minister Mikhail Bogdanov told Russian news agencies that supplying S-300 to Syria is Russia's "own right" and expressed confidence that this would not hurt Russia's ties with Israel.
The Syrian military has already been trained to use the system, which was set to be sent over in 2013, but was held up "at the request of Israel", Shoigu said.
They also said radar and communication systems will be added near Syria to monitor potential attacks.
U.S. National Security Adviser John Bolton said on Monday that Russian plans to supply Syria with an S-300 missile system would be a "significant escalation" by Moscow and that he hopes it will reconsider.
In denying responsibility for the incident, Israel blamed Syria and its allies Iran and Hezbollah.
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She added: There's so many people to thank - I'm extremely grateful because this is my first project and I appreciate your support.
The Kremlin also accused Israeli pilots of "premeditated actions", warning the incident would harm relations between the two countries. Russian Federation laid the blame on Israel, saying Israeli fighter jets had pushed the plane into Syria's line of fire.
The Russian government has agreed to provide the regime of Syrian President Bashar al-Assad with a missile defense system, according to the BBC.
Konashenkov said the Russian military received a call from Israeli command at 1839 GMT on the day of the incident to warn that Israel would be striking "north of Syria", where the Il-20 surveillance aircraft was monitoring the Idlib de-escalation zone.
On Sunday, military spokesman Igor Konashenkov presented the results of an investigation. Russian Federation has agreed to supply the Syrian government with a surface-to-air missile defense system as it continues to try to prop up the regime there. He said USA troops would stay active in Syria as long as Iran was involved.
According to the halturnerradioshow.com, nearly seven Ilyushin Il-76 military transporters of Russian Air Force have arrived at Khmeimim military airbase on 22 September.
A spokesperson for the Israeli army on Monday declined to comment on Moscow's S-300 delivery.
"According to information of our military experts, the reason [behind the downing] was premeditated actions by Israeli pilots which certainly can not but harm our relations", Kremlin spokesman Dmitry Peskov was quoted as telling journalists.
FILE - A photo taken on July 23, 2006 shows an Russian IL-20M plane landing at an unknown location.