The CNN host reacted to Madonna joining Twitter for one day in promotion for her album MDNA by reiterating that he will never agree to interview her.
"Welcome to Twitter @MadonnaMDNAday - you're still banned from my show. Love Piers," Morgan tweeted.
Oseary - who has managed Madonna for many years - replied to Morgan by writing "Really??" and attaching an image of an October 2011 request from Morgan's producers to interview the 'Girl Gone Wild' star for his UK series Life Stories.
Morgan responded by clearing up any confusion about his stance on chatting with Madonna.
"Madonna's only been banned from my #CNN show @guyoseary - not my UK show, which sent that invite. But I'm now banning her from that too," Morgan wrote.
He then added: "Oh, and I'm afraid you're banned from all my shows too @guyoseary - guilt by association, sorry."
Morgan has publicly ridiculed Madonna on several occasions in recent years. The journalist described the popstar as "annoying" last March and more recently condemned her Super Bowl half-time performance.
Piers Morgan Tonight is broadcast weeknights at 9pm ET on CNN and at 8pm BST on CNN International.
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Watch Madonna's 'Girl Gone Wild' lyric music video below: