After failing to boost Russia's fertility rate via pro-natalist policies and to extend life expectancies, Putin "seems to have concluded that the only way to achieve a sizable increase in his population is by annexing and subordinating ethnically and culturally related neighbors, by force if necessary."

The PM will meet troops from the UK-led Nato battlegroup in Estonia as he warns Russia is the "most acute threat" the UK faces

Vladimir Putin has been warned Russian military personnel and equipment is now “stranded” in Syria after the dramatic collapse of Bashar al-Assad’s regime. The dictator fled the country’s capital, Damascus, at the weekend and has been flown to Moscow at the personal insistence of Putin himself.