The X Factor is to be screened three times in one week later this month with an extra edition lined up to clash with the launch night of Strictly Come Dancing as rivalry between the shows hots up.

ITV bosses said they had had to add an extra Friday night show as a result of other shows on the network which have squeezed the time available.

But it means the singing contest will go head-to-head with the BBC One show as the couples make their dancefloor debuts together on September 26.

The shows have had one battle already this year, when Strictly was the clear winner on September 7 with a scene-setter programme in which contestants were unveiled and paired off with their professional partners.

X Factor boss Simon Cowell conceded the day after - when overnight ratings showed the BBC programme's average audience was 800,000 ahead - that Strictly had won "round one".

Now ITV has confirmed that the boot camp and judges' houses stages of their annual talent hunt will play across three consecutive nights, rather than having just the Saturday and Sunday night editions.

The launch of a new Sunday night variety show on the channel as well as the screening of period drama Downton Abbey mean only one hour is available on the Sunday so the decision has been made to add the Friday edition.

An ITV insider said: "The plan to strip boot camp and judges houses' across three nights has been in place for some time.

"Boot camp and judges houses are always longer shows, and this year we don't have the space to accommodate a long show on Sundays for these stages, so we have decided instead to strip the shows across three nights."

But the BBC pointed to the fact that ITV would long have known that its rival was a long-standing fixture.

A BBC insider said: "It's very odd as they claim they are doing everything they can to avoid clashes but are playing X Factor on a Friday night for the first time ever when Strictly's first live show has been on Fridays for years."

The schedules are to be finalised later today but are unlikely to change, with both X Factor and Strictly pencilled in for 9pm starts on September 26.