An ITV documentary due to air next week claims to have uncovered evidence of “race hatred, religious bigotry, and extreme rightwing activism” at a number of UK charities.

The filmmakers will also claim that the Charity Commission told them it was "powerless" to respond to the behaviour within the charities, a claim the Charity Commission disputes.

Charities Behaving Badly is set to air on ITV on Wednesday 18 February as part of its Exposure series.

ITV says that reporters went undercover for “almost a year” with three separate charities, all registered with the Charity Commission, and found “shocking evidence of racism and admiration for terrorism”.

The broadcaster alleges that at one charity, trustees and supporters were using “slogans relating to Hitler’s Mein Kampf” and shouting “white power” chants.

In the second charity, it says children are apparently taught about “Christian conspiracies” against Hinduism and are told that Islam is “the worst religion in the world”.

In the third charity, workers reportedly sang the praises of radical preachers and openly discussed the option of going to Syria for the purposes of jihad.

The filmmakers also claim that representatives of the Charity Commission told them they are "powerless to de-register a charity, just because they are 'ineffective or troubling'".

The Charity Commission disputes these claims and said it is already looking into the charities identified by ITV.

A Charity Commission spokeswoman said: “We are already taking action in relation to a number of concerns raised with us as a result of undercover filming in charities undertaken by a TV production company.

"We remain in contact with the filmmakers regarding the final broadcast and have requested all footage. We will issue an update on our regulatory action when appropriate to do so.”