MOSCOW: Russia's military on Friday said a US strike on a regime air base in Syria was ineffective but announced Syrian air defences would be strengthened to shield the country's key infrastructure.
"To protect Syria's most sensitive infrastructure, a complex of measures will be implemented in the near future to strengthen and improve the effectiveness of the Syrian armed forces' air defence system," defence ministry spokesman Igor Konashenkov said in a statement.
He added the strike had had an "extremely low" military impact, and fewer than half of the 59 reported US missiles had actually found their target.
"Only 23 missiles reached the Syrian airbase," he said.
The strike on the Shayrat airbase, ordered by US President Donald Trump, destroyed six planes under repair and several buildings, including a storage depot and radio station, he said.
"The runway, taxi ways and Syrian airforce planes at parking spaces are not damaged," he said.
"The military effectiveness of the massive US missile strike on the Syrian airbase is therefore extremely low."
Separately, the Russian state channel Rossiya24, in a report from the base, said nine planes, as well as munition and fuel depots, had been destroyed but the facility's runway was intact.
Konashenkov's statement said the attack was a "gross violation" of a US-Russian memorandum aimed at avoiding clashes over Syria.
Moscow announced earlier it was halting the deal reached in 2015 in response to the strike, despite Kremlin spokesman Dmitry Peskov confirming the US side had warned Russia of the impending attack through the channels it had established.
Trump ordered the strike -- Washington's first direct military action against President Bashar Assad's government -- in response to what he called a "barbaric" chemical attack this week that he blamed on Damascus.
Moscow has been flying a bombing campaign in support of Syrian forces since September 2015 and has sought to deflect blame from its ally over the alleged chemical attack.