Vladimir Putin came in from the cold as relations between Moscow and Western leaders thawed over a combined desire to see the terrorist hate group wiped off the face of the earth.
The move comes as Britain is poised to join the growing number of countries committed to obliterating ISIS from the air.
Mr Putin and French President Francois Hollande, who have enjoyed an increasingly warm relationship in the aftermath of the horrific Paris attacks, reached the breakthrough compromise during crunch talks last night.
Russian leader even had warm words for the US-led coalition - set to include the UK - and offered to temporarily put aside political differences for the greater good.
He said: ”We view the US-led coalition with respect and stand ready to cooperate with it.
“We believe that we would better create a single, united coalition as it would be easier, simpler and more efficient to coordinate our work that way.
“If our partners aren't ready for that, OK, we are ready to work in a different format that is acceptable to our partners. We are ready to cooperate with the U.S.-led coalition."
ISIS has claimed responsibility for deadly attacks against both French and Russian citizens in recent weeks.
On November 13 the terror hate group carried out gun and suicide bomb attacks in Paris killing 130 people.
Weeks earlier the terrorists smuggled a bomb on board an airliner which blew up over Egypt’s Sinai peninsula, killing 224 predominantly Russian passengers and crew.
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