Justice Secretary Chris Grayling has said he plans to fight "for every penny" that the Ministry of Justice was allegedly overcharged for electronic tagging services.
Earlier he said that a government-commissioned audit suggested that the incorrect bills ran into the "low tens of millions" and that he would take "all necessary steps" to get a refund for taxpayers.
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Philip Hammond has dismissed concerns that abolishing stamp duty for first-time buyers will push up house prices.
Elsewhere it will be largely sunny, though with gusty winds at times, and a few showers likely in places.
Heavy rain has caused widespread flooding and travel disruption across north west England and North Wales.