A newly-released Us Weekly report cites a supposed insider claim that Clooney and Keibler's relationship has "run its course" and that they are near a split.
An informant disclosed: "They have little in common. She likes to go out and have fun. She's been feeling the age difference."
Keibler's alleged inability to fit in with Clooney's older friends was also cited as a reason for the relationship trouble.
A spokesperson for Clooney responded to the tabloid article by insisting to Gossip Cop that the actor and Keibler are not having any relationship problems.
"What makes up this s**t?" Clooney's representative quipped.
Clooney denied similar claims in January that his busy acting schedule was leaving little time for him to spend with Keibler.
The pair were first linked in the press in 2011, when Keibler was spotted on holiday with Clooney in Lake Como, Italy.
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