AceShowbiz - Rap superstar Jay-Z has kept his promise to put Lily Allen's imminent retirement from pop on hiatus - the singer has confirmed she will open for the rapper at a top U.K. music festival in summer. The hip-hop mogul recently admitted he'd like to collaborate with the "Smile" singer before she steps out of the music industry in March.

And although Allen previously insisted she will be focusing on fashion ventures after completing her tour with Dizzee Rascal next month, Jay-Z has persuaded her to perform one more gig - at London's Wireless festival in July. The singer insists teaming up with the "99 Problems" hitmaker is the perfect end to her pop career.

She says, "I was very flattered to hear that Jay-Z wanted me to support him at Wireless and, combined with my dates in March with Dizzee Rascal, I am excited to end my current string of live shows in such prestigious company."

In a post on her Twitter.com page, she adds, "I'm slightly delaying my retirement till June (sic). My last gig will be supporting Jay-Z at Wireless in London." Allen's last stage performance will come on America's Independence Day, July 4.