Russell Brand has been shopping for a diamond ring - sparking rumors he is going to propose to girlfriend Katy Perry.

The British comic star was photographed looking at bands at exclusive London jewelers Cartier last Friday with one specific sparkler catching his eye. “His face lit up when he saw this one particular diamond ring. He put it on his ring finger and gazed at it for ages,” a source said.

Russell, 34, has been dating Katy, 25, since September and it looks as though he is ready to turn his back on his womanizing ways for good and settle down with the “I Kissed a Girl” singer.

Earlier this week, the Forgetting Sarah Marshall star admitted he is a changed man since meeting the pop beauty. Russell - who is a former heroin addict and alcoholic - said:

“She’s ‘The One’. I’m a one-woman gentleman now. She’s amazing. I’m having a right laugh, she’s a good person to spend time with and it’s changed me, it’s made me stop doing stuff that I probably shouldn’t have been doing. I didn’t drink or take drugs, my main hobby was meeting girls and chatting them up. Once you stop doing that, everything’s a lot more relaxing. Now I’m just talking to people, I do a bit of yoga, meditate, look out the window, think about the cat. It’s a more chilled out pace of life.”