Lindsay Lohan is Wearing a Wedding Ring!

Lindsay Lohan has fuelled rumours her romance with Samantha Ronson is back on - by flashing a "wedding ring" during her visit to London.

The singer/actress was on a low-key trip to the U.K. while Ronson was in London for a series of DJ gigs this weekend.

And gossips were sent into a spin when Lohan hit the city's clubs on Saturday evening - proudly showing off a gleaming band on the third finger of her left hand as she left the Bungalow 8 nightspot.

An onlooker says, "Lindsay has gone to extraordinary lengths not to be photographed with Samantha during their visit to London, but after a few drinks she clearly let her guard down. She was holding her hand up for the cameras to get a clear shot of the ring and didn't seem to care who noticed."

Lohan and Ronson split in March after a series of furious bust-ups. Last month, the Mean Girls star's dad Michael Lohan spoke out to warn his daughter that getting back together with Ronson could ruin her career.