The new definition could make it illegal to criticise Muslim traditions and would clash with existing equality law

Anti-terrorist operations would be hampered if Theresa May bows to pressure to create an official definition of Islamophobia, the leader of Britain’s police chiefs has warned.

Martin Hewitt, chairman of the National Police Chiefs’ Council (NPCC), said that the reform, proposed by backbench MPs and peers, risked exacerbating community tensions and undermining counterterrorist policing powers and tactics. His intervention comes in a letter to the prime minister, seen by The Times.

Ministers will respond in parliament tomorrow to a backbench debate on the definition. It states: “Islamophobia is rooted in racism and is a type of racism that targets expressions of Muslimness or perceived Muslimness.”

The wording has been accepted by Labour, the Liberal Democrats and Sadiq Khan, the Mayor of London.

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