Russia has launched co-ordinated missile strikes against rebels in Syria, with Moscow for the first time using its only aircraft carrier in combat, Defence Minister Sergei Shoigu says.
Shoigu said on Tuesday a frigate had fired cruise missiles, jets from the Admiral Kuznetsov, Russia's sole aircraft carrier, had been involved in action, and missiles had been loosed from a mobile land-based missile system inside Syria.
In Washington, Captain Jeff Davis, a Pentagon spokesman, said he was aware of the announcement, but was still looking into the strikes.
"From a pure military perspective, Russia already has significant capabilities inside Syria," Davis said.
"Anything that they bring in from the outside, if it's aircraft carriers or if it's cruise missiles launching from ships or if it's long-range strike bombers flying in from Russia, those are done for show."
Reporting to President Vladimir Putin in southern Russia, Shoigu said Russia had targeted sites associated with Islamic State and the Nusra Front, which has changed its name to Fateh al-Sham, in the Homs and Idlib provinces. "We carried out exhaustive advance research on all targets," said Shoigu.
"We are talking about warehouses with ammunition, terrorist training centres ... and factories." Shoigu said the strikes would continue. He made no mention of Aleppo, where a civil defence official and a resident said air strikes had struck several districts in the rebel-held east of the city for the first time in weeks.
Syrian state television said Syria's air force carried out strikes on Aleppo on Tuesday. Russia says its air force is for now honouring a unilateral moratorium on hitting rebel targets inside Aleppo.
In Geneva, meanwhile, two UN agencies said food production in Syria has shrunk to "an highest low," threatening to drive more people from their homes after 5-1/2 years of war.
The World Food Program and the Food and Agricultural Organisation said factors like rising prices, poor weather, general instability and the lack of fertiliser and seeds could force some farmers to stop producing.
A joint report released Tuesday says the planting area in the 2015-2016 season was the smallest ever in zones controlled by the government, ethnic Kurds and the armed opposition. WFP spokeswoman Bettina Luescher said information was lacking about areas controlled by IS.
FAO regional representative Abdessalam Ould Ahmed said 80 per cent of households in Syria lack food or money to buy it.