Rule 11 of the Air Navigation order states that an aircraft which is being overtaken in the air shall have the right-of-way.
ICAO states that an overtaking situation exists when the overtaking aircraft is within an angle of less than 70 degrees from the extended centreline of the aircraft being overtaken
Air Navigation order – Section 4 rule 11
Overtaking is complete once the overtaking aircraft is passed and clear, as determined by the pilot of that aircraft.
