Elton John is holding nothing back in his opinion of Madonna. The famous pop singer took a swipe at John's son Zachary's godmother, and he hasn't forgotten about it. "She's been so horrible to Gaga," he told an Australian television show called 'Sunday Night' on Sunday night, referring to Lady Gaga

“She’s such a nightmare. Her career’s over...and she looks like a f---ing fairground stripper," he added.

The famous piano man also said Madonna's tour is a disaster. "If Madonna had any common sense she would have made a record like (1998's) 'Ray Of Light' and stayed away from the dance stuff and just been a great pop singer and make great pop records, which she does brilliantly," he added (quote via NME.com).

The two have a checkered history, including a jab from Elton John before she performed at the 2012 Superbowl. John has been making headlines for reasons other than music lately. Last month he and partner David Furnish revealed they're expecting another baby via surrogate. In fact, they're using the same surrogate who gave birth to Zachary in 2010.

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