Growing threat: counter-terrorism officers at the scene of June’s extremist attack at London Bridge

Ministers are to plough an extra £50m into counter-terrorist policing after the Home Office asked for more money to deal with the “fast-changing” threat to Britain.

Philip Hammond, the chancellor, has struck a deal with Amber Rudd, the home secretary, to raise the Home Office budget from £707m to £757m next year.

The rise follows warnings from police and security services of a step change in the threat from Islamist terrorism this year. MI5 said recently that the security services have managed to thwart nine terrorist attacks on home soil since March. The Tories were criticised by Jeremy Corbyn, the Labour leader, in the general election this summer for cutting the number of police officers on Britain’s streets.

Senior government sources said the new money