Police are expected to respond to a 999 call within 12 minutes

The number of incidents Metropolitan Police officers get to within the recommended 12 minutes has dropped to an average of 71% - down 1.3%.

The number of 999 calls also increased by 3% in 2003 with 84.9% of them answered within 15 seconds.

Scotland Yard said response times should improve with changes being made to the way calls are assessed.

The figures compiled by the Metropolitan Police Authority (MPA) show that responses within the 12-minute target vary from borough to borough.

People have been paying extra council tax and the mayor's proclaiming extra policemen, but if the service is actually going down then the thing isn't working Eric Ollerenshaw, Conservative London Assembly View the complete list here

Among the slowest is Hounslow at 58.1% and Bromley at 61.5%.

But callers in Westminster and Kensington and Chelsea get a better service with more than 80% of responses within the target.

The report says one reason for the decline may be the increase in police recruits.

Last month Metropolitan police numbers reached 30,000 and the MPA report says there are more probationers than ever before.

In the space of 20 months the proportion of probationers has increased from one out of every five officers to just under one in three.

Eric Ollerenshaw, the Conservative leader in the London Assembly, told BBC London the police force was not giving value for money.

Changes being introduced

"At the end of the day people have been paying extra council tax and the mayor's proclaiming extra policemen, but if the service is actually going down then the thing isn't working," he said.

But Commander Bob Broadhurst of the Metropolitan Police told BBC London response times varied according to the circumstances of the day.

"It might be officers available on that particular day, it could be the vehicle fleet. It only takes one vehicle to be out of action.

"We are dealing now with an unprecedented number of calls - 136,000 more calls last year."

Police chiefs argue that changes being introduced should improve the way the urgency of each call is assessed.