Moscow has transferred three advanced S-300PM anti-aircraft batteries to the Syrian regime, Russian news outlet Izvestia reported on Friday.

The S-300PM is more sophisticated than the S-300 system transferred to Syria earlier this month and was delivered together with mobile radar stations, the report said.

The Russian Defense Ministry downplayed concerns that the Iranians would use the advanced systems, claiming they lack the technical expertise to operate a system such as the S-300PM.

According to the ministry, only the Russian military has experts with the know-how to operate the sophisticated system, and they intend to strictly compartmentalize the transfer of technical knowledge to the Syrians.

“The Iranians have no ability to use the system. The anti-aircraft systems we transferred to [the Syrians] in the past are compatible for export and the needs of Iran and are completely different. The systems we are transferring to the Syrians were built for the Russian military and it alone has the know-how and capability to operate them at the moment,” the ministry told Izvestia in a statement.