Donald Trump has been booked to appear on David Letterman's first new Late Show in weeks - if the show returns on January 2 as currently scheduled.

Talks between Worldwide Pants, which produces both Letterman's Late Show and Craig Ferguson's Late Late Show for CBS, and the WGA have begun but no resolution has been reached so far.

When asked for comment, the WGA said only that a "lively exchange of information took place".

Were an agreement to be reached, it would give CBS a competitive edge over NBC, where Jay Leno and Conan O'Brien will be returning with new episodes of their respective programmes also on January 2 but without monologue-creating writers.

Talks are expected to continue after Christmas Day.