Boris Johnson has pledged to "name and shame" London boroughs which fail to crack down on binge drinking and alcohol-related violence.

The Conservative mayoral candidate warned on Wednesday that town centres often became "no-go areas"  and said it was "time to get tough on bars and shops that break the rules" by removing their licence.

Claiming that drink was implicated in 40 per cent of violent crime incidents, he highlighted Metropolitan Police figures showing a 13.7 per cent increase in violent offences since 2000.

"In addition to getting more police on the streets, we need to tackle the problem at its core and get tough with bars and shops that break the rules," he said.

"We must make alcohol harder to buy for under-18s in order to tackle the problem of underage drinking and deal with alcohol-related violence.

"I am willing to publish league tables, naming and shaming those councils who do not use their new powers to crackdown on this."

Johnson also said he would "use my influence" as chairman of the Metropolitan Police Authority to ensure that police officers "take a more proactive approach" in tackling underage drinking.

Green vote

Meanwhile, Green Party candidate Sian Berry has urged supporters to vote Labour's Ken Livingstone as their second choice.

Livingstone also said he would give his second vote to the Greens, and launched a joint green agenda with Berry.

The pair said they would maintain the congestion zone and introduce a £25 charge for high emitting vehicles, extend the low emission zone to cover lorries over 3.5 tonnes, oppose further airport and work towards a target for 50 per of new homes to be affordable.

"Tackling climate change and creating a fairer London must be at the top of any serious mayor's agenda," they said in a joint statement.

"Boris Johnson, who supported George W Bush in opposing the Kyoto Treaty and would scrap the CO2 charge on gas guzzlers, cannot be trusted with London's environment.

"Nor can a man who opposed the minimum wage be expected to promote fairness or tackle poverty. London – with a committed mayor and Green Party representation on its assembly – has taken a global lead on environmental and social justice over the last eight years. Let's keep it that way."