“Apologists” for those who commit acts of terrorism are partly responsible for the violence, Philip Hammond will say.
Security services have been criticised over their handling of Mohammed Emwazi – known as “Jihadi John”.
But in a speech later the foreign secretary will praise the “brilliance” of Britain’s intelligence officers.
He will also say ministers must act “decisively” in debates about powers given to the security services so they can “get on” with keeping the UK safe.
Speaking at the Royal United Services Institute in London, Mr Hammond will say: “We are absolutely clear; the responsibility for acts of terror rests with those who commit them.
“But a huge burden of responsibility also lies with those who act as apologists for them.”