British opposition leader Jeremy Corbyn says there should be a communications channel created with the Islamic State group in hopes of ending the war in Syria.

The Labour leader told the BBC on Sunday that a back channel — similar to the one created with the Irish Republican Army during the decades-long conflict in Northern Ireland — should be established. Corbyn says "There has to be a route through somewhere," particularly given that some IS commanders are former officers in the Iraqi Army.

He says "there has to be some understanding of where their strong points are, where their weak points are."

Corbyn also reiterated his long-standing opposition to Britain's Trident nuclear deterrent and suggested that submarines could be deployed without nuclear warheads on them.