The British Army could take up to two years to get back to normal after stepping in to cover the shortfall in Olympic security.
Speaking to The Guardian the military's chief planner for London 2012 said 18,000 troops were deployed - many at short notice and diverted from their usual duties.
Wing Commander Peter Daulby also warned that reducing the size of the military could put Britain at risk of not coping with civil emergencies.
More top news
Investigators have released images of two more people they wish to speak to about the Hillsborough tragedy.
The number of reported anti-semitic incidents in the UK have increased by just over 50%, figures released by a charity have suggested.
Athletes competing at next years Summer Olympic Games in Rio de Janeiro will be using waters contaminated with human feces, a study finds.