Mayor Boris offers to be sprayed by water cannon in safety move

Mr Johnson denied “playing politics” by purchasing the riot control equipment before its use on the streets of mainland Britain has been approved by Home Secretary Theresa May.

Mr Johnson and Mrs May have been identified in polls as leading rivals to succeed David Cameron as Conservative leader, but the Mayor insisted his decision was not an act of defiance to the Home Secretary at a time when she has been embroiled in a public row over extremism in schools.

He told LBC 97.3 radio that by spending £130,000 on buying, refitting and transporting three second-hand vehicles from German police now, before they are approved for use, he will save Londoners £2.4 million in the long term. Water cannon have never been used on the British mainland, although they have been used in Northern Ireland.

But the Metropolitan Police concluded there could be a limited role for the tactic in the wake of the 2011 riots, and Mr Johnson believes there is broad support from Londoners.

Mrs May insisted that she would carry out a “proper” consideration of the health and safety implications of water cannon before reaching a decision.

But the Mayor’s Office for Policing and Crime said the German authorities had threatened to sell them elsewhere if the deal was not completed by July.

Challenged to be filmed standing in front of the water cannon, Mr Johnson initially seemed reluctant. But after a few moments’ consideration, he came round to the idea, saying: “Alright, you’ve challenged me to this. I suppose I’m going to have to do it now.”

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