[b]
Channel 4 has said it is in talks to commission further series of reality show Big Brother.
But the programme's producers, Endemol, have said discussions are on hold until the sixth series ends this summer.
A spokeswoman for Endemol dismissed reports that another multi-series deal is being signed as "speculation".
The current agreement between Channel 4 and Endemol for the show, which has proved a ratings hit, is due to expire with the conclusion of Big Brother 6.
Celebrity spin-off
The station signed the deal with Endemol in 2002, which gave it the rights to the show and has become an important revenue raiser.
The conclusion of last year's series, which saw Portuguese transsexual Nadia Alamada triumph, attracted nine million viewers - and was a vast improvement on the previous series.
But the format, which also has a successful celebrity spin-off, has been criticised by some commentators as low-grade television and even cruel.
Academic Germaine Greer, who walked out of Celebrity Big Brother earlier this year, accused the show of adopting "superior" bullying tactics and treating the contestants "irresponsibly".
Broadcaster John Humphrys denounced reality TV as "seedy, cynical and harmful" to society at last year's Edinburgh Television Festival.
A more "evil" Big Brother in the most recent series even saw a fight break out between some of the housemates, which led to complaints from the public and a rebuke from broadcasting watchdog Ofcom.
BBC