Scotland Yard needs more resources to tackle the terrorist threat to London, Deputy Assistant Commissioner Brian Paddick has said.
This would improve intelligence work and investigations of any future terror acts, he told BBC Radio Five Live.
Along with planned changes to terror legislation, it would "make London a far safer place", Mr Paddick said.
Proposals in the government's Terrorism Bill include extending pre-charge detention from 14 days to three months.
Mr Paddick said: "The government is helping us by changes in legislation and we hope to put a convincing case to government for additional resources, [which] put together with the changes in legislation will help to make London a far safer place."
Scotland Yard and the Metropolitan Police Authority were putting together a joint bid for more funding, he said.
"We need more officers to join with their colleagues who are already working hard to try and make London safer in the light of what appears to be an increased threat, not only in London but across the world.
"We need additional resources to provide more resilience around our ability to both capture intelligence about potential bombings in the future, but also to increase our resilience around our ability to investigate this sort of offence."
Al-Qaeda has claimed responsibility for the 7 July suicide bombings in London, in which 52 people were killed.
The first payments have been made to victims of the bombings, the Criminal Injuries Compensation Authority has said.
So far it has offered 14 payments to bereaved relatives and eight to injured survivors, more than £400,000 in total.