The former Labour Prime Minister, who now works as a peace envoy to the Middle East on behalf of the UN, the US, the EU and Russia, described the Islamist ideology allegedly behind the attack on the off-duty British soldier last month as "profound and dangerous".
Writing in the Mail on Sunday, Mr Blair, a Catholic convert and founder of the Tony Blair Faith Foundation, said that although there was no problem with Muslims in general, "there is a problem within Islam - from the adherents of an ideology that is a strain within Islam."
"At the extreme end of the spectrum are terrorists," he said, adding "by and large we don't admit it".