The American funnywoman, who has battled clinical depression, has been a long-time campaigner for a number of organisations and is the patron for the British Neuroscience Association.

Wax will now be feted for her work by U.K. monarch Queen Elizabeth II, who will award her a special OBE for foreign nationals.

In a post on Twitter.com, the star writes, "Ahem. I've got something exciting to tell you... I'm going to be awarded an OBE for my services to mental health... Thank you so much to all of you who have come on this journey with me - together we can remove stigma about mental health."

A number of stars have since congratulated Wax on the news in messages posted on her website.

Sir Ian McKellen writes, "Well deserved congratulations to Ruby", while Star Wars legend Carrie Fisher, adds, "Fantastic news! Does this mean she's a Dame?" Other stars to have posted messages include singer Annie Lennox and actress Joanna Lumley.