In a statement, Blair said: "Jack's contribution to law and order in Britain and this country's standing in the world is quite simply formidable.
"In 2015, Parliament will lose one of the most able politicians of my generation, but I have no doubt that he will be immensely successful in whatever he turns his hand to next."
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A teenager who grew an incredible 10cm overnight after an operation to correct a curve in her spine has been given the all clear by doctors.
Severe weather warnings have been issued for northern England and Scotland, where it could drop to minus 10C (14F) in some places.
Expect it to feel colder with a biting, bitter windchill, this Valentine's Day.