A voluntary scheme aimed at slashing the sale of super-strength alcohol has been launched in Portsmouth.

The city council and Hampshire Police are asking retailers to stop selling beers, lagers and ciders with an alcohol volume of above 6.5%.

It is hoped the scheme will cut anti-social behaviour, which the council believes costs the city more than £70m a year.

If a store signs up to the scheme its alcohol licence is changed so that it is prohibited from selling super-strength products. A similar scheme has been introduced in Ipswich.

So far, 25 Portsmouth retailers have agreed to the scheme, including Howard Toms of Spar Eastney. He said: “Customers are often aggressive and that’s not what I want in the store.”

Panchanalingham Aranan of New Kwiki Mart Stores in Southsea said that he had signed up even though he believed he would lose sales.

But Linda Sood of Falcon News in Portsmouth said the scheme would alienate responsible customers who bought those products.

She also expressed concern that only independent retailers were being asked to sign up. “None of the multiples or pubs seem to be involved in this,” she said. “Why is the focus and responsibility placed just on us?”

Inspector Claire Taylor of Hampshire Police said it was “not just about targeting shops”.