The idealogy behind ISIS and other extremist Islamic groups has wide support in mainstream Muslim communities, Tony Blair warned yesterday.

The former British prime minister used a speech at the memorial of 9/11 in New York to suggest that, although only a minority take up arms and join extremist groups, the radical views behind them are widely held.

"The conspiracy theories which illuminate much of the jihadi writings have significant support even amongst parts of the mainstream population of some Muslim countries," he said.

"There are millions of schoolchildren every day in countries round the world – not just in the Middle East – who are taught a view of the world and of their religion which is narrow-minded, prejudicial and therefore, in the context of a globalised world, dangerous."

Blair, who has been a peace envoy to the Middle East and has just taken a new role with the European Council tackling anti-Semitism, said that many Muslims feel the West is hostile to Islam.

"If large numbers of people really do believe that the desire of the USA or the West is to disrespect or oppress Islam, then it is not surprising that some find recourse to violence acceptable in order to re-assert the 'dignity' of the oppressed," he said in his speech.

"If young people are educated that Jews are evil or that anyone who holds a different view of religion is an enemy, it is obvious that this prejudice will give rise, in certain circumstances, to action in accordance with it.

"The reality is that in parts of the Muslim community a discourse has grown up which is profoundly hostile to peaceful coexistence. Countering this is an essential part of fighting extremism."

However, although he argued extremist ideology was widespread, Blair he said it was not representative of true Islam.

The violence of Islamic extremists "no more represents the true spirit of Islam than atrocities executed in the name of Christianity in days gone by, represented true Christian faith," he said.

Blair cited a new report by his think-tank, the Faith Foundation, entitled 'Inside the Jihadi Mind' in arguing that alliances needed to be made with Muslims who are outraged at the hijacking of their religion.

The "majority of Muslims detest this extremism and are the main victims of it," he said, while highlighting those that subscribe to a "liberal and modern interpretation" of Sharia.

"We don't face a clash of civilisations or of faiths; but a pernicious and false ideology which is a denial of civilisation and a perversion and not an expression of faith," he said.

"The challenge is from within Islam. The solution is also from within Islam."