Kidman's ring a clue

Nicole Kidman has been spotted with a ring on her wedding finger while walking with her latest beau, Keith Urban, sparking rumours she is engaged to the country-music singer.

People magazine reports that the actress, who began dating fellow Aussie Urban in July, was seen strolling along a Boston street wearing the ring.

Spokespeople for Urban and Kidman said they knew nothing about a proposal, but a source close to Urban described the pair as "inseparable".