The star, who recently announced she will make her West End theatre debut later this year when she takes on the lead role in The Bodyguard musical, was singing alongside pop band The Feeling.
The 40-year-old, who grew up in Penn Fields, was also joined on stage by the actor Dominic West, who starred in The Wire, for a crowd-pleasing performance of Blur's Parklife.
The event was organised as part of a four-day trade show for companies holding the Royal Warrant, including Kidderminster's Brintons Carpets and West Midlands carmaker Jaguar Land Rover, which is taking place as part of a 60th anniversary Coronation Festival.
Other stars who performed on the night included Katherine Jenkins, Katie Melua, Russell Watson and opera legend Dame Kiri Te Kanawa.
