SINGAPORE - There will be restrictions on flights in and out of Singapore during the upcoming US-North Korea summit.

A notice to airlines and pilots issued by Singapore aviation authorities and posted by the International Civil Aviation Organization (Icao) and the US Federal Aviation Administration (FAA) on their websites, said that airspace over Singapore will be temporarily restricted for parts of June 11, 12 and 13.

The meeting between US President Donald Trump and North Korea's Chairman of the State Affairs Commission Kim Jong Un will take place on June 12.

Flights arriving into Singapore Changi Airport will be required to reduce speed and face some restrictions on runway use "for reasons of national security", the notice said.

Separately, a statement from the Civil Aviation Authority of Singapore (CAAS) and the Ministry of Defence (Mindef) confirmed that airspace restrictions over Singapore will be in place from 8am on June 10 to midnight on June 14.

"Travellers are advised to expect delays for flights arriving at and departing from Singapore during this period," the statement said.

On average, a flight lands or takes off from Changi Airport every 1 1/2 minutes and shorter, during peak periods.