Leaders of the world's leading economies will renew pressure on Russia to act over the crisis in Ukraine at a summit in Brussels today.
The G7 group of economic powers will also try to thrash out the outline of an agreement over tackling the threat from terror posed by the Syrian conflict.
David Cameron will push for more action to bolster border security and warn that the threat poses a challenge and risk to all.
G7 leaders effectively expelled the Russian Federation from the annual gathering of the top industrialised nations, which it had been due to host, over its actions in Ukraine.
During a working dinner tonight, they will set out demands for Vladimir Putin to work with newly elected Ukrainian president Petro Poroshenko to deescalate the crisis.
But although European leaders and US president Barack Obama have said they stand ready to impose tougher sanctions on Moscow, a fresh wave of penalties is not expected to be announced.
Leaders will focus on how to support Mr Poroshenko and how to tackle long-standing problems with corruption in Ukraine as well as its ailing economy.
They will discuss sending a “very clear message” to Mr Putin that he must engage with Kiev and use his influence on the rebel separatists in eastern Ukraine, sources said.
Mr Cameron is due to then hold face-to-face talks with the Russian president over the Ukraine crisis when the two leaders attend commemorations of the 70th anniversary of the D-Day landings in Normandy on Friday.
Moscow's annexation of Crimea led to the suspension of Russia, due to host the planned G8 summit in Sochi, from the group and a hastily arranged meeting is now being staged in in Brussels.
It will be the first G7 since the summit staged in Lyon, France in 1996.
The group will dismiss the sham presidential elections being staged by Bashar al -Assad and underline previous demands that the Syrian president must go.
But it will also look at ways to curb the impact on national security posed by foreign fighters in the region, although detailed agreements are not expected.
Although the summit has been “pulled together at relatively short notice”, sources insisted the substance will still focus on core G7 business — including foreign affairs, the global economy and trade.
PA