The new restrictions came into force from today.
The Civil Aviation Authority, National Air Traffic Services (NATS) and the Ministry of Defence have worked together to inform airspace users about the restrictions and how people can continue to use UK airspace during the Olympics, the MOD said in a statement.
Equipment and personnel from the Royal Navy, Army and Royal Air Force is in place to enforce the restrictions and provide enhanced protection for the period the temporary restrictions are in force, the MOD added.
London's already crowded airspace will see an additional 4,000 flights crossing its paths in the week coming up to the Olympics and during special events like the opening and closing ceremonies, Paul Haskins of NATS said.
The new flight restrictions add to the high level military presence around Olympic games venues which saw missile launchers being placed in a south east Londonsuburb.
The government on Thursday also announced 3,500 troops were being deployed as extra security cover.
The move brings the total number of military personnel including reservists protecting the games to 17,000.
The substantial security operation for the Olympics also will feature 12,000 police, 3,000 volunteers, Typhoon fighter jets, helicopters, two warships and bomb disposal experts.