The Tokyo Metropolitan Police Department has mobilized 16,000 officers - or one third of its entire workforce - for the visit of US President Barack Obama.

Security has been reinforced at Haneda Airport, where Obama is expected to land on Wednesday evening.

The airport's observation deck and other areas will be closed during the president's arrival.

Officers are also patrolling around the clock the areas surrounding the US Embassy and the State Guest House in central Tokyo.

A large portion of the Japanese capital's highways will remain closed throughout Obama's visit.

Residents are encouraged to use public transportation as much as possible.