British troops are to be deployed to the Baltics as part of a long-term Nato mission to deter Russian aggression.
Defence Secretary Michael Fallon said a "small number" of soldiers would be stationed there to "watch over our allies on the eastern borders".
RAF Typhoon fighters are already in the region as part of the Baltic Air Policing detachment and have been called into action in recent months.
Civilians are being killed by Russian airstrikes and military intervention in Syria, Defence Secretary Micheal Fallon has said.
Mr Fallon said the the "vast majority" of strikes since Vladmir Putin authorised raids in the war-torn country had not been against Islamic State jihadists but were instead "killing civilians" and the Free Syrian forces rebelling against Bashar Assad's brutal regime.
He said that Russia's military intervention in Syria was propping up Assad rather than tackling the treat from the so-called Islamic State.
Fallon acknowledged the Russian involvement had "complicated" the situation but indicated he still believed that Britain should extend its own bombing campaign to target IS in Syria.
In an interview with The Sun he said initial Ministry of Defence intelligence suggested only one in 20 Russian air strikes so far were on targets to damage IS.
He said: "We're analysing where the strikes are going every morning. The vast majority are not against IS at all.
"Our evidence indicates they are dropping unguided munitions in civilian areas, killing civilians, and they are dropping them against the Free Syrian forces fighting Assad.
"He's shoring up Assad and perpetuating the suffering."
Incursions by Russian jets into Turkish airspace have prompted a stern response from Nato's most powerful ally.
Here's what you need to know about this latest development in the increasingly bloody, complicated and volatile conflict.
Russia urges world leaders to unite to fight terrorism in Syria amid criticism that air strikes have targetted rebel fighters and civilians.