Jennifer Aniston and Jennifer Lopez are said to be embroiled in a bitter feud over their upcoming movies, according to a new report.

It's claimed tensions have been simmering between the former Friends star and J-Lo  ever since it emerged that both women are set to star on the big screen as single mothers.

Jennifer is said to be worried that Hollywood's golden girl will steal the romcom spotlight from her with her oh-so-similar mummy-movie.

"The last thing J-Lo wants is to have Aniston overshadow her," a source tells the Daily Mail.

"There’s been some mud-slinging, with J-Lo claiming Jen took her idea."

Newly-single Jen is currently shooting The Baster with Jason Bateman in New York, while Jennifer is due to begin filming on her comeback movie Plan B later this year.

See Jennifer Aniston on set below