Merton police are among the hardest in London to get hold of for non-emergency calls, according to a survey by the Liberal Democrats.

The survey by the London Assembly's Lib Dems found that of 141 stations they tried to contact with non-emergency calls, there were responses from only 76, or just over half.

Merton was named as one ofthe worst performing boroughs, along with Hammersmith and Fulham, where researchers say they were unable to get through to any of the local police stations.

But nearby Kingston was among the best, where all their calls were answered.

A similar exercise in 2003 had better results with a 61 per cent response rate.

In the 2003 survey, 80 police stations out of a total of 132 answered out-of-hours calls.

The Metropolitan Police said it was delivering a programme aiming to improve the way it handled all non-emergency calls.

"Four years on from our last survey, these results show the Met to be more distant and uncontactable," Lib Dem Dee Doocey said.

"Londoners face silence at the end of the line for just under half the capital's police stations, a disgrace by any standards."

The best performing boroughs, with all calls answered, were Kingston, Barking and Dagenham, Brent and Waltham Forest.

A Met police spokesman said: "The survey conducted focused on non-emergency, and non-crime reporting, and as such would have been transferred within the police station at the discretion of the operator."

The spokesman said the improved call handling would include a system in which the caller was directed to an individual or to a voicemail system for similar enquiries.