Anthony Joshua has been warned to focus on his next fight with Joseph Parker rather than a potential clash with American heavyweight champion Deontay Wilder.

Joshua currently holds the World Boxing Association (WBA), International Boxing Federation (IBF) and International Boxing Organization (IBO) heavyweight titles and is set to put them on the line on March 31 against World Boxing Organization (WBO) heavyweight champion Joseph Parker in a title unification clash.

The winner of the fight in Cardiff's Principality Stadium will not only hold four titles but also keep their unbeaten record intact as a meeting with World Boxing Council (WBC) heavyweight champion Wilder will ideally be next in line.

Anthony Joshua and Joseph Parker Anthony Joshua and Joseph Parker square up during a press conference at the Dorchester Hotel in London, England, Jan. 16, 2018. Photo: Justin Setterfield/Getty Images

While Parker will be a big test for the Briton, the bigger title unification fight right now is arguably between Joshua and Wilder who have been calling each other out for some time now. With talks and reports on a potential fight being negotiated between the duo, Parker's promoter David Higgins feels "AJ" is underestimating his fighter and should do so only at his own risk.

"All this talk about Deontay Wilder, I think Anthony Joshua looks past Joseph Parker at his peril," Higgins told Sky Sports. "Anthony Joshua's making a grave mistake, if he's looking past Parker. It's one thing to quietly analyze future possibilities, but if they are going any further and are in the early stage of negotiations, it's far too early for any of that."

"I don't think Joseph Parker or [his coach] Kevin Barry will be the slightest bit concerned that the Joshua camp are discussing all these other possibilities when they've got an unbeaten world champion in front of him, who has never been dropped in his life, and is lightning fast with his hands, and has great footwork."

As for how the training camp for Joshua is going for the New Zealander, Higgins adds that Parker is firing on all cylinders. He also believes Parker will not be fazed by the prospect of fighting in front of potentially 80,000 plus fans as the villain.

"He is firing on all cylinders. This camp is the best he's had," Higgins explained. "I talk to Kevin and Joe most days and there is a calm, confident air. Everything is on song, the combinations are being put together. He's quick, he's sparring lots of rounds, and everyone is happy. We're on the home straight and everything is on song."

"This talk of Joe being overawed about being in the U.K. with 80,000, that doesn't worry him at all. People don't know him if they say that. He fought on the [Wladimir] Klitschko undercard in Germany at a sold out event. The most unflappable guy you will meet. He knows that my job as a promoter is about making a deal, that's all done. He knows he is the only one in the ropes and he is focused only on Anthony Joshua. He's not talking about Deontay Wilder, he's focused on Anthony Joshua, and he knows what his job is — it is to beat Anthony Joshua."

Deontay Wilder Deontay Wilder poses with trainer Marc Breland after knocking out Luis Ortiz in the tenth round of their WBC Heavyweight Championship fight at Barclays Center in the Brooklyn Borough of New York City, March 3, 2018. Photo: Al Bello/Getty Images

As for Wilder, he will be keeping a close eye on the contest, having recently passed his biggest test on March 3 after defeating Luis Ortiz via 10th round TKO in Brooklyn, New York.

The "Bronze Bomber" claimed he would be attending the fight between Joshua and Parker, with Sky Sports hiring him as a commentator.