2008-06-03 08:35:24 - Justin Timberlake has been shopping for an engagement ring so he can propose to Jessica Biel.

Justin Timberlake has been shopping for an engagement ring. The singer is planning to propose to Jessica Biel and is asking her close friends to help him choose the perfect diamond band. A pal of Jessica's

told the Chicago Sun Times newspaper: "Justin has been ring shopping, and we're talking serious, major Harry Winston-type shopping here. "He has been quizzing Jessica's closest pals and associates, trying to get a take on the kind of engagement rings she has admired. The only comment I ever heard Jessica make was when she complimented a mutual friend's square-cut emerald ring - when a girlfriend of ours got engaged. It was huge!" Justin's friends claim the 'SexyBack' singer realised he wanted to take his relationship with Jessica to the next level after their busy work schedules kept them apart for long periods. Last month, it was claimed Justin was ready to marry Jessica on the privately owned island of Mustique in the West Indies. A source said: "Justin is 27 and thinking about marriage and kids. For the first time in his life he is feeling settled and has definitely decided to pop the question to Jessica."