CM Punk has been long linked with a return to WWE. 

Ever since he left the company in 2014, some fans have been desperately calling for his comeback. 

In years gone by it seemed almost impossible. But now, with the relationship between Punk and WWE mended, it's not out of the question. 

After all, The Best in the World is a regular guest on Fox Sports' WWE Backstage show, which would suggest he's willing to be involved with the company in some capacity. 

However, don't get your hopes up for an in-ring return just yet, because according to Dave Meltzer and Bryan Alvarez, there's still a lot of bitterness between the two parties.

Most of it though comes from WWE, rather than Punk. 

"I do know that WWE is pretty negative on the idea of Punk wrestling, more than I thought they would be but they are," Meltzer said on a recent edition of Wrestling Observer Radio, per NoDQ.

"I think the idea is between Bill Goldberg and Edge and Undertaker and people like that, they’ve got their fair share of guys like that. 

"There’s a lot of bitterness. Apparently there’s more bitterness on the WWE side right now than on the Punk side. I would have thought it would be the other way around."

Alvarez added that Punk's recent social media activity hasn't exactly helped the relationship. 

"Well, he has taken plenty of shots on Twitter. He even gave away the June date for WrestleMania, back when that was being rumoured."

It's certainly interesting to hear suggestions that WWE are the bitter party, rather than Punk.

Surely, even Vince McMahon and the company's hierarchy know just how big of a draw the seven-time world champion is?

There may still be bitterness there, but it certainly wouldn't be wise to rule out a return on that, especially as it sounds like Punk is ready to put the past behind him.