Russian defense ministry says a special 'hotline' establish to avoid fighter jet dogfights in Syria, where it is propping up Assad.

Russia's defense ministry said Thursday that its forces in Syria had set up a "hotline" with Israel's military to avoid clashes in the sky over the war-torn country.

"Mutual information-sharing on the actions of aircraft has been established through a hotline between the Russian aviation command center at the Hmeimim air base and a command post of the Israeli air force," ministry spokesman Igor Konashenkov was quoted as saying by Interfaxnews agency.

The spokesman added that the two sides were undergoing training on how to cooperate.

Russia has deployed a huge military presence in Syria over the last two weeks, to prop up the regime of Bashar al-Assad with a campaign of airstrikes it claims targets Islamic State (ISIS), but which Western officials have revealed is in fact almost exclusively focused on anti-Assad rebels, including those backed by the West.

An American defense official on Wednesday said the US and Russia are nearing a pact on safety protocols to avoid outright warfare between American and Russian troops in the war-torn state, in a similar manner to the steps being taken with Israel.

The fighting in Syria has frequently affected Israel, with "spillover" mortar fire onto the Golan Heights becoming a common occurrence.

The most recent such incident took place this Tuesday, and the IDF responded by striking Syrian army sites, holding the regime responsible for attacks emanating from its sovereign territory.

AFP contributed to this report.