Rihanna allegedly banned UK’s X-Factor winner Alexandra Burke from meeting Chris Brown over the weekend in London.

That’s right. Chris’ Umbrella girlfriend heard Alexandra tried to arrange a meeting through her record label Sony, which she shares with Brown and Rihanna immediately vetoed the rendez-vous.

"Alex was mortified," a source tells Britain’s Daily Mirror. "She had no idea she had been banned from meeting her idol. She's a massive fan of Chris Brown - she said numerous times on The X Factor how much she fancies him and wants to meet him."

Apparently, Alexandra had watched Brown's concert, along with her siblings Aaron, David, Sheneice and her mentor Cheryl Cole in the VIP box. After the concert Alexandra thought was scheduled to meet Chris at the after party. However, thanks to Rihanna, she couldn’t even get in!

“Alexandra was later turned away once Rihanna heard about Burke's crush on her man she pulled the plug on any meeting," reports the Mirror.

As previously reported, the Disturbia star gave her beau strict instructions on what he could and couldn’t do while on tour. (Although, meeting contest winners wasn’t on the list, Rihanna clearly made an addendum this weekend.)

Alexandra’s career has been on the upswing since her X-Factor win. Her cover of Hallejuah ended 2008 as the biggest selling UK single and she’s rumored to open for Beyonce (her other idol) on several tour dates. Unfortunately, one thing she will not do is meet Chris Brown if Rihanna has anything to do with it. rihannaforum.com