Robert Pattinson and Justin Theroux have become friends

Jennifer Aniston and fiancé Justin Theroux are planning a double date with newly-reunited couple Robert Pattinson and Kristen Stewart.

Justin and Robert are believed to have met at US TV host Jimmy Kimmel‘s Emmys after party last month and bonded over their love of fast bikes.

‘They hit it off talking about motorbikes,’ a source tells the Daily Mirror.

Jennifer, 43, became engaged to Justin on his 41st birthday in August and showed off a huge diamond ring on her left hand during a day out in New Mexico last week.

She welled up as she spoke about the moment Justin got down on one knee during an interview on friend Chelsea Handler‘s chat show this Monday.

‘You guys make the greatest couple ever,’ said Chelsea, 37, as Jen wiped away tears.

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Anna Duff