'Bridget Jones' Baby' is in "aggressive development".

Renee Zellweger

Renee Zellweger

Renee Zellweger and Colin Firth are in final negotiations to return to the film series as the titular heroine and love interest Mark Darcy, while director Sharon Maguire - who directed 'Bridget Jones' Diary' in 2001 - is already contracted to make the movie and is currently assembling a key crew and searching for locations across the UK ahead of proposed filming in autumn.

Eric Fellner, co-chairman of production company Working Title, told the Daily Mail newspaper:

"We are keen to try to make it later this year, but there's still nothing definite yet.

"If the script and all our deals with the actors fall into place, then this one will be up and running."

Fellner and Maguire have held extensive meetings with the two leads, and also been in contact with other actors from the film series, including Gemma Jones and Jim Broadbent, who played Bridget's parents.

However, Hugh Grant will not be returning as Daniel Cleaver, nor will the role be re-cast.

The film is based on columns written by author Helen Fielding eight years ago, not her most recent novel 'Mad About the Boy' - in which Bridget is struggling as a single mother following Mark's death - and the writer penned the initial screenplay with David Nicholls.