A Russian pilot tried to shoot down an RAF spy plane believing he had been given permission to fire, reports say.
Russia had blamed a "technical malfunction" for causing the incident over the Black Sea on 29 September last year.
But the BBC reports that according to sources with knowledge of the incident, Russian communications intercepted by the RAF Rivet Joint aircraft paint a very different picture.
Intercepted communications suggest the Russian pilot launched a missile after receiving an ambiguous command from a Russian ground station, the BBC said.
The RAF RC-135 Rivet Joint had been flying a surveillance mission in international airspace when it encountered two Russian Su-27s.
A Western defence source told the BBC the words the two Russian pilots received were to the effect of "you have the target".
One pilot interpreted this as permission to shoot, but the other did not, swearing at his wingman when he fired the missile, according to the report.
Sources said the unclear language indicated a high degree of unprofessionalism by those involved and led to a fight between the two pilots.
The air-to-air missile that was launched failed to lock on to its target, the report said.
But despite his comrade reprimanding him, the pilot then released another missile which fell from the wing, suggesting the weapon either malfunctioned or the launch was aborted, according to the report.
The RAF aircraft is equipped with sensors to intercept communications, and the crew would have been able to listen to the incident, but these details will not be made public.
A Ministry of Defence spokesman said: "Following an incident last September between an RAF Rivet Joint aircraft and two Russian Su-27 fighter jets over the Black Sea, the former defence secretary informed the House of Commons within three weeks of the event occurring, in the interest of transparency and safety.
"Our intent has always been to protect the safety of our operations, avoid unnecessary escalation and inform the public and international community.
"This incident is a stark reminder of the potential consequences of [Russian President Vladimir] Putin’s barbaric invasion of Ukraine."
Then-defence secretary Ben Wallace made a statement in the Commons following the incident, telling MPs it showed the Russian military were "not beyond making the wrong calculation or indeed deciding that the rules don’t apply to them".
He added: "We welcome Russia’s acknowledgement this was in international airspace, and the UK has conducted regular sorties with the RAF Rivet Joint in international airspace over the Black Sea since 2019 and we will continue to do so."