The rollout of the Airwave police radio network has been criticised by the London Assembly for not providing enough coverage.

A report by the Assembly's 7th July Review Committee last year said poor communication delayed rescue efforts in the aftermath of the London Underground bombings in 2005.

Problems with the network need to be continually addressed as the system is rolled out, according to committee chairman Richard Barnes.

'Our report highlights continuing problems with Airwave that need to be tackled to ensure emergency service personnel have access to the robust and effective communications systems they need,' he said.

The original contract for the network was signed by the now-defunct Police IT Organisation (Pito) in 2000, but the rollout has still not been completed.

The network has no coverage in buildings, vehicles and some areas of the underground, says the report.

Additional coverage will be provided at an extra cost for crucial areas such as Wembley and Heathrow.

Trials by The Metropolitan Police have shown up problems above ground. Some radios have unexpectedly reset themselves, and batteries have run out prematurely. the Met told the committee.

In November last year Computing reported that the backup power supplies for the network will last only around five hours despite government contingency guidelines which specified businesses should plan for blackouts lasting up to three days.