It all started with a simple birthday wish from one Marvel Comics hero to another. Now the tongue-in-cheek war of words is on for Deadpool 2's Ryan Reynolds and Logan's Hugh Jackman.Reynolds, who celebrated his 42nd birthday on Tuesday, seems to be feeling a bit salty about the greeting he received from the longtime Wolverine actor. Fans got to watch as the exchange unfolded on Twitter, as Jackman wrote, "Because I'm told that I AM THE NICEST GUY and you're NOT [...[ I will let you hug me. Just this once. On your birthday."RELATED: Ryan Reynolds Has a New Plan to Get Hugh Jackman in a Deadpool MovieA few hours later, Reynolds returned the volley with his own tweet, calling Jackman a "monster" who has hidden his true nationality from the world.

"He's not even from Australia," the actor wrote. "He's from Milwaukee."

The history of good-natured ribbing between the pair goes way back to 2011's X-Men Origins: Wolverine, and is essentially rooted in Reynolds's determination to have Jackman appear as Wolverine in a Deadpool film. Jackman has made it known that the 2017 hit Logan, his ninth appearance in that role, is the last time he intends to don the famous adamantium claws. However, Reynolds continues to campaign for a change of heart.

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There have been occasional cracks in Jackman's stance on the subject, with various interviews in recent years revealing that he regrets never appearing in a Deadpool or Avengers movie, but for the time being it looks like Reynolds will have to carry on lampooning his friend and hoping for the best.

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