The overlap will cause further bad blood between the channels after weeks of friction over the scheduling of the two shows.
ITV had recently moved the audition heats of BGT to a later Saturday night slot after it was repeatedly beaten in the ratings. Last week it finally edged ahead of the BBC1 show by a small margin thanks to its later time.
But as both sides revealed their schedules for Saturday, May 13, it emerged that ITV had pulled forward once more to screen the 150-minute final of BGT at 6.30pm.
Schedulers from the BBC have been battling throughout the afternoon to work out how to respond, but eventually settled on 6.10pm. ITV claimed the timing was comparable to previous slots for the final of BGT.
But BBC bosses are understood to be angered by the move, particularly after ITV chiefs were said to have blown their tops when The Voice overran by three minutes last month causing the two shows to overlap.
They feel that ITV has been provocative with its scheduling by screening the show two hours and 10 minutes earlier than this Saturday’s edition of the programme.
A BBC insider said: “This isn’t about winning the ratings battle for us because we know the final will be popular, it’s just that this is a completely avoidable situation. They could have played it later.
“ITV’s claims about ‘dirty tricks’ with the three-minute overrun now look rather disingenuous.”
An ITV source said: “We are screening the final in a similar slot to previous years, and we have to accommodate rather a long family show.”