Aircraft that stray into the restricted airspace around the Olympic Park could be subject to "lethal force" if they fail to comply with directions from military aircraft.
Puma helicopters, with on-board snipers, and RAF Typhoon fighter jets will be patrolling the restricted zone from midnight tonight, when it comes into force.
Unauthorised aircraft will be intercepted and expected to comply with directions from military aircraft, first rocking their wings, then following the military plane or helicopter away from London.
If the aircraft does not cooperate, flares and lasers could be fired and then - as a last resort - lethal force could be authorised.
Asked who would give the order for lethal force, Air Vice-Marshal Stuart Atha said: "The highest level of Government makes that decision."
He said taking lethal action would be a "worst-case scenario" and that a best-case scenario would be to intercept and gain knowledge of the seriousness of the situation away from the built-up area of London.
The restricted zone is made up of a small inner zone, covering central London and the Olympic site in Stratford, and a large zone covering a swathe of south-east England.
Under the plans, general aviation will not be allowed in the inner zone, although passenger planes heading for Heathrow and London City Airports will not be affected.
Private pilots wanting to fly in the larger restricted zone will have to file a flight plan and comply with Ministry of Defence instructions.
The Civil Aviation Authority has written to all private pilots and distributed more than 60,000 leaflets to warn them about the restrictions.