The Royal Air Force of the United Kingdom (RAF) submitted a request to one of the most combative Air Forces on the planet, and thus Greek F-16 fighters were found in Romania to train with British Eurofighter Typhoons.
In particular, the announcement of Hellenic National Defense General Staff states:

“On Thursday, July 28, 2022, at the request of the Royal Air Force of the United Kingdom (RAF), Dissimilar Air Combat Training (DACT) between 2 F-16 BLOCK 52+ Fighter Aircraft of the Hellenic Air Force was conducted at Bucharest FIR Aviation with 2 Eurofighter Fighter Aircraft of the RAF.
This activity contributes to the upgrading of the multi-level military synergy of the Armed Forces of the NATO Member States, promoting the level of operational readiness, combat capability and cooperation of the participants in an allied context” the announcement concludes.
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