Tony Blair will urge the West today to reach out to Vladimir Putin in the fight against radical Islam, despite the Russian president's militant stance over Ukraine.
The West must put aside differences with Russia over Ukraine to focus on tackling the threat from radical Islam, the former prime minister will warn.
It is unknown what the former Labour leader would like to happen to the people of Ukraine and Crimea in the interim.
Highlighting the "growing" danger from religious extremism – and the West's apparent "reluctance" to fight it – the former prime minister is to call for it to be elevated to the "top of the agenda", rather than the ensuing crisis in Ukraine.
Blair’s criticism of politicians being uncomfortable talking about religion comes after Prime Minister David Cameron ran into criticism for speaking about his Christian faith and characterising Britain as a Christian country.
Failing to "take sides" with moderates in the Middle East and North Africa could mean the 21st century is dominated by conflict rather than peaceful co-existence, Blair will say.
“We have to stop treating each country on the basis of whatever seems to make for the easiest life for us at any one time. We have to have an approach to the region that is coherent and sees it as a whole,” he will say.
Ahead of the speech, Blair – a peace envoy – also warned the West would pay a "very heavy price" for not intervening in Syria.
The politician is due to make the intervention in a speech at Bloomberg in London this morning.
It comes with tensions still running high in eastern Ukraine, and after Russia was jettisoned from the G8 group of nations over Vladimir Putin's decision to annexe the Crimea.
But Blair will describe a wider crisis with its roots in "a radicalised and politicised view of Islam, an ideology that distorts and warps Islam's true message".
"The threat of this radical Islam is not abating. It is growing. It is spreading across the world.
"It is destabilising communities and even nations. It is undermining the possibility of peaceful co-existence in an era of globalisation.
"And in the face of this threat we seem curiously reluctant to acknowledge it and powerless to counter it effectively."
He will call on leaders to consider the "absurdity" of spending billions of dollars on security against an ideology which is being "advocated" in the schools and institutions of "countries with whom we have intimate security and defence relationships".
Speaking to the BBC ahead of the speech he said the West had a "responsibility but also an interest" in making sure that "huge struggle" was "resolved in the right way".
"However much people may think we can just push it to one side and forget about it, I think that would be a mistake.
"Above all, we have to commit. We have to engage."