Jennifer Aniston is planning a three-day wedding.

The former 'Friends' actress had initially planned a small, intimate ceremony for when she ties the knot with Justin Theroux but the couple's celebration ideas are growing increasingly more ''extravagant''.

A source told the UK edition of Grazia magazine: ''What started out as quite low-key is now looking more extravagant.

''They are still keen on a beach wedding in Hawaii or Mexico towards the end of the year, but Jen wants it to be more like a massive party and, at the moment, it looks like it could stretch over three days. Half of Hollywood will be there too.''

After Jennifer - who was previously wed to Brad Pitt - showed off her eight-carat emerald-cut diamond for the first time last week, there is now speculation she will break from her usual simple, classic style choices when choosing her wedding dress.

A source said: ''The dress is being kept top secret. But now Jen's debuted this massive ring, it's kind of set a precedent so who knows, we could see Jen break from her conservative, simple style and go for a show-stopper of a dress too.''