Countries must devote more resources to fight global extremism, US Secretary of State John Kerry said on Friday, but the battle would falter if it becomes consumed by sectarian division.

Speaking against a backdrop of deadly Islamist militant attacks in France, Pakistan, Nigeria and elsewhere, Kerry told leaders at the annual World Economic Forum: "These kinds of actions can never be excused. And they have to be opposed. With every fiber of our being, they have to be stopped."

"We have to take risks, we have to invest more resources," he said.

Shortly before, President Francois Hollande of France, which is still reeling from the killing of 17 people by Islamist gunmen in Paris two weeks ago, urged global business leaders to help fight terrorism by cracking down on money laundering and trafficking.

Kerry also announced he would travel on Sunday to Nigeria, Africa's most populous country battered by an Islamist Boko Haram insurgency that has killed thousands of people.

State Department spokeswoman Marie Harf said Kerry would meet Nigerian President Goodluck Jonathan, who is running for re-election on February 14 amid criticism over his handling of the insurgency threatening Nigeria as a unified state.

Kerry described Islamic State militants, who have seized wide swathes of Iraq and Syria, as "a collection of monsters". He said ultra-radical groups like Islamic State and Boko Haram "are attempting to govern land. It’s a first-time event".

He compared efforts to curb the spread of extremist violence to the fight against fascism in World War Two. "The first step is to make clear the civilised world will not cower in the face of this violence," he said.

Kerry made no specific new proposals for how to counter the tide of violent militancy. US President Barack Obama has invited allies to a Washington summit on the issue on February 18.

Saying world leaders must "keep our heads," Kerry warned: "The biggest error that we could make would be to blame Muslims collectively for crimes not committed by Muslims alone.

"Unless we direct our energies in the right direction, we may very well fuel the very fires we want to put out," he said. "There’s no room for sectarian division, there’s no room for anti-Semitism or Islamophobia."-Reuters