John Mayer is on a quest to find Jennifer Aniston the perfect engagement ring, if reports are anything to go by.

The singer and his showbiz girlfriend 'outed' their commitment to one another last month at the Oscars with a joint interview, and now it seems they are ready to go one step further.

John has allegedly approached top US jeweller Lorraine Schwartz - who has crafted one of-a-kind rings for Jennifer Lopez, Heidi Klum and Beyonce - for the perfect ring for his bride-to-be.

A pal close to the couple tells the Mirror: "Money is no object for John. He is creating a vintage-style classic ring for Jen. He's looking at 18-carat flawless diamond so he wont get much change from £2million.

"When he does get down on one knee he wants to be completely sure he gets the right answer. He knows a ring like that would be hard to refuse."

An insider adds, "He's just waiting for the most romantic setting to put the ring on her finger - busy schedules permitting."

If Jen accepts John's proposal this will be the second time everyone's favourite Friend walks down the aisle - after divorcing Brad Pitt in 2005.

See Johnnifer's love story below