LONDON — British Prime Minister David Cameron is defending a letter sent to senior Muslims explaining "how faith in Islam can be part of British identity."

The note was sent to 1,000 Islamic leaders from Communities Secretary Eric Pickles, who writes that he is proud of the reaction of British communities following the Charlie Hebdo attacks in Paris, but he insists in the letter that there is more work to do.

"We must show our young people, who may be targeted, that extremists have nothing to offer them," the letter reads.

"We must show them the multitude of statements of condemnation from British Muslims, show them these men of hate have no place in our mosques or any place of worship, and that they do not speak for Muslims in Britain or anywhere in the world."

The letter then tells faith leaders they have "an important responsibility: in explaining and demonstrating how faith in Islam can be a part of British society."

Harun Khan, deputy secretary general of the Muslim Council of Britain, hit back at the letter. "Is Mr. Pickles seriously suggesting, as do members of the far right, that Muslims and Islam are inherently apart from British society?" he asked.

Cameron, however, defended the publication, saying Pickles was "absolutely right" to write the letter urging leaders to do more to tackle extremism. Cameron said the letter was "reasonable, sensible and moderate."

Former Chief Rabbi Lord Sacks said he thought the letter was "well-intentioned," but he questioned the idea that Muslim leaders should be held responsible for extremism.

"That letter suggested the Muslim community within Britain can contain its own radicals," he told BBC Radio 4's Today programme. "The truth is that Islamism, like all modern global political movements, is actually a global phenomenon — transmitted by the Internet and social media."