The pair, who have known each other for several years, were snapped as they left the exclusive Groucho Club at 2.50am today (12 June).
Sarah had opted for a sexy biker chick look, with a pair of leather skinny trousers, a quilted leather jacket and a leopard print blouse.
The Girls Aloud star kept her blonde hair loose with a small clip and teamed her outfit with a towering pair of pale yellow peep toe heels and an orange pedicure.
Capital FM DJ Greg, meanwhile, kept it casual by wearing a pair of jeans, a T-shirt and checked shirt combo, and a pair of brown lace-ups.
Although they were holding hands, Sarah and Greg are just good friends who often hang out together.
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