Messi, currently on €13 million-a-year, has seen Ronaldo's salary jump from €11 million to a staggering €21 million.
AS says Messi is now pushing to renegotiate his contract to get closer to Ronaldo's terms.
A Barca source said: "We do not knowing anything about those intentions.
"We know that the player is happy, but we do not talk to him every day about these matters."
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