Barnet Police has been criticised for its “unacceptable” failure to meet target attendance times between November and January.
The force is expected to reach 90 per cent of emergency calls, such as serious assaults and robberies, within 15 minutes, and attend 90 per cent of urgent calls, such as burglaries or reports of theft, within one hour.
But between November and January, attendance times dropped below those figures.
Labour GLA member Andrew Dismore blamed the failure to meet the targets on financial cuts imposed by London Mayor Boris Johnson, and warned the situation will only get worse.
The former Hendon MP said: “This is unacceptable and a clear consequence of the 20 per cent cuts imposed by Mayor Johnson on the Met.
“I have previously released the officer number figures, which show how many fewer officers we now have compared to 2010, when the Conservative-led coalition came to power.
“The cuts are now showing in poor performance figures. I understand that Barnet’s attendance times for January were the second worst borough in the whole of the Met.”
In November, the percentage of target times met for emergency and urgent calls were 87.7 and 86.2 respectively.
In December, they were 89.3 and 85.5 per cent, while in January, they remained below the 90 per cent target at 89.5 and 88.3.
Mr Dismore added: “It might not sound a lot but it matters a great deal if you are the one being assaulted on the street or whose house is being burgled.
“Fifteen minutes is not exactly a short time either – the fire service has six minute targets to reach a call.”
Barnet Police insisted the mayor’s new policing plan would lead to more officer numbers on the front line (compared to 2011) and denied the failure to meet target times was due to a lack of police officers.
Barnet Superintendent Simon Corkill said: “For the year to date (between April and January) Barnet Borough's emergency immediate call response is 90.9 per cent and significant (urgent) is 90.3% - both above the target.
“In the period November to January, the statistics we provided do show that the borough did not meet the targets but do show improvement. This had nothing to do with the number of police officers as the new model for policing that went live in June provides an increase in front line police numbers.
“There are a range of operational reasons for not meeting the target, ranging from fleet availability to a surge in call demand. These are assessed throughout the day and changes to our deployments made.”