The Home Secretary told the House of Commons she had "long been concerned about the use of stop and search".
Theresa May said: "While it is undoubtedly an important police power, when it is misused stop and search can be counter-productive
"First, it can be an enormous waste of police time. Second, when innocent people are stopped and searched for no good reason, it is hugely damaging to the relationship between the police and the public. In those circumstances it is an unacceptable affront to justice."
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The Prime Minister will urge leaders of the other 27 EU states to move on as quickly as possible to talks on Britain's future trade.
Despite temperatures reaching double figures in the south today, it was still a chilly day, with brisk winds.
The four-time Tour de France winner has said he has always taken great care to stay within the rules after returning an adverse urine test.