Treasury Chief Secretary Danny Alexander announced the money yesterday to help 400,000 more families deemed to be at risk of social collapse.

The Government is already targeting the 120,000 worst failing mums and dads - like Frank Gallagher in TV's Shameless - to try to turn their lives around.

Problem families cost taxpayers up to £100,000 a year EACH because of bills they rack up with the police, courts, NHS and social services.

A one-off investment of £4,500 to help just one family with difficulties saves £15,000 a year, officials say.

Mr Alexander said: "This is an example of how, by spending a bit more in certain areas, we can save much more in others."