Alicia Keys treated her entourage to nine magnums of champagne last night (27.05.10).

The pregnant singer - who is engaged to music producer Swizz Beats - celebrated her happy news at London nightspot Merah, but made sure she stuck to cranberry juice all night.

A source said: "She treated her entourage to nine magnums of Dom Perignon champagne, whilst she remained on cranberry juice all night.

"She arrived at the club with Swizz Beats, who was dressed very smartly in black tie and they gazed adoringly at each other in the V.I.P. area.

"Her baby bump was carefully concealed underneath a flowing black dress and practically the whole club stood still to see Alicia toasting her baby news with her man sat beside her and with all her friends sat around her table."

However, Alicia - who was joined in her celebration by Black Eyed Peas star, Sugababes singer Jade Ewen and shoe designer Christian Louboutin - cut short her night, complaining of tiredness.

The source added to BANG Showbiz: "Alicia's party arrived at the club at around 1.30am and stayed for just over an hour because Alicia complained of feeling exhausted but she thanked staff on the way out for looking after her so well. The rest of her party stayed on to the end of the night."