A Qatari fighter jet flew within almost 200m of a UAE civilian aircraft while flying over Bahrain on Sunday.
The aircraft was carrying 86 passengers - including seven children - and was traveling a pre-approved route, state news agency Wam reported.
The jet - a Mirage 2000 - reportedly flew within three vertical kilometres and 215 horizontal metres of the civilian registered aircraft.
It is the fifth time a Qatari aircraft approaches a UAE plane while flying an approved route over a country's airspace.
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The UAE's General Civil Aviation Authority said the maneuver left just seconds before the collision of the two aircraft, endangering the lives of those on board.
"We will file a complaint with the International Civil Aviation Organisation (ICAO) regarding this infringement," the GCAA said.
"The threat of passenger safety in any way is unacceptable.The incident is a clear repetition of the threat to the safety of civil aviation and a violation of international laws and conventions," it said in a statement.
In an interview with Sky News Arabia, Saif Al Suwaidi, director general of the GCAA, described the incident as "the greatest form of terrorism: using military weapons against civilians".
He said the UAE would be filing another official complaint with the International Civil Aviation Organisation, a UN specialised agency.
Mirage 2000 jets can fly up to 2,400kph, Mr Al Suwaidi said, and should the jet have intended to move closer to the aircraft: "a collision could have occurred within just a blink of an eye.
"A fighter jet flying that close to a defenceless civilian aircraft is an act of intimidation and a show of power.
“If this is not stopped from happening again it could lead to an accident,” he said.
Last month, Qatari fighter jets came within just 200 metres of a UAE-registered aircraft in what was described as a dangerous escalation of the harassment of the Emirates by the country's civil aviation authority.
The UAE, along with Saudi Arabia, Bahrain and Egypt, have imposed travel, diplomatic and trade sanctions on Qatar since last June, accusing it of supporting terrorism.