Actor Robert Pattinson and singer FKA twigs have pushed back their wedding because the latter can't decide whether she wants a low-key event or an elaborate affair.

A source close to the couple told people.com that the wedding plans have been pushed back "until autumn at the earliest" because the bride-to-be "can't decide what (kind of) wedding she'd like to have".

"She talks about it keeping as real and low-key and then wants an elaborate glamorous baroque affair. She was even talking at one stage about having a masked ball. It will now be bigger but how big, nobody's quite sure at this moment in time, there's no fixed date but will probably be late in the year," added the source.

Pattinson and twigs (nee Tahliah Barnett) got engaged earlier this year after dating for six months.