Big Bang Theory stars yet to sign new contracts
The original five cast members of The Big Bang Theory are still without contracts, two weeks ahead of the start of shooting of the eighth series.
Warner Bros TV has so far failed to reach any agreement with Jim Parsons, Johnny Galecki, Kaley Cuoco, Simon Helberg and Kunal Nayyar over salaries.
Production may be delayed if new deals are not reached in the next two weeks.
According to the Hollywood Reporter, though, the cast are still expected to return to work.
The long-running CBS sitcom was extended for a further three series earlier this year.
The show, which centres on a group of high-functioning science "geeks", will now air until at least 2017.
The Hollywood Reporter claims that Parsons, Galecki and Cuoco currently earn $325,000 (£190,000) per episode and are now seeking up to $1m (£584,000) per show.
Such a deal would make them the highest paid actors on US television - ahead of Ashton Kutcher and Jon Cryer from Two and a Half Men, currently understood to be the most rewarded TV actors.