Michael Howard will today call for common sense and honesty in sentencing through the introduction of US-style mandatory minimum sentences and an increase in the number of prisons.

"Everyone knows that prisoners rarely, if ever, serve the sentences that are handed out by the judges," he will say.

"Criminals sentenced to less than four years are automatically out after serving just half their sentences. Nothing does more to undermine confidence in our criminal justice system."

Howard will also resurrect the prospect of the "three strikes and you're out" policy he pursued as home secretary.

The Tory leadership has announced, however, that it will oppose the government's plans for ID cards following a backbench revolt over Howard's support for the measure.

Meanwhile major Tory donor Stewart Wheeler has urged the Conservative leader to stay out of the public eye because voters don't like him.

Wheeler said: "He doesn't want to go rushing off to constituencies up and down the country.

"He should not spend time doing that. They [the public] don't warm to him. Blair gets people to warm to him and Michael finds that difficult."