Piers Morgan has welcomed Madonna to Twitter by banning her from his show. The CNN host used the "Hung Up" hitmaker's debut on the microblogging site yesterday to inform her she will never be welcome as a guest on his program.

"Welcome to Twitter. You're still banned from my show. Love Piers X," he wrote.

But the 53-year-old's manager Guy Oseary, Tweeted back, "Really?" along with a letter from Pier's UK show asking Madonna to appear.

"Madonna has only been banned from my CNN show, not my UK show, which sent that invite. But I'm now banning her from that too. Oh, and I'm afraid you're banned from all my shows too @guyoseary- guilt by association, sorry," Piers explained, defending himself.

According to TMZ.com, Madonna - who joined Twitter for one day only to promote her new album MDNA - doesn't know what sparked the feud. "She doesn't even know who he is," a source said.

Piers has previously revealed the bad feelings stem back to his days as an editor for the Daily Mirror newspaper. "Madonna and I, we've never really seen eye-to-eye. There was a bread roll throwing incident in London in the mid 90s; there was an incident at a hotel in the south of France [at] the Cannes Film Festival involving a photographer and a bodyguard; there's been an incident involving a pub owned by her recently departed husband, Guy Ritchie, where my brother was the manager. You know the worst thing Madonna did to me? Madonna's publicist once said to me, 'Listen to me, Madonna is not pregnant,' when I was running a newspaper. And I said, 'Are you sure?' She said, 'Listen to me, Piers. Madonna is not pregnant.' The next day, they announced [the news] on a rival newspaper's website. There's a series of crimes," he told Access Hollywood.

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