The WBA 'super' and IBF champion is fully focused on his unification clash with WBO title holder Joseph Parker on March 31 as he can move one belt away from becoming undisputed champion, Sky Sports reported.
WBC king Wilder will be watching from ringside as part of the Sky Sports team, but Joshua said the American should think twice about stepping between the ropes if he defeats the New Zealander in Cardiff.
Joshua exclusively told Sky Sports, "He's been at my [Wladimir] Klitschko fight and I've watched him in Sheffield when he fought Audley Harrison.
"He's flying over to come and watch me fight Joseph Parker, and this is what it's about – it's building up to that big clash.
"I'm a unified heavyweight champion. We're talking about undisputed heavyweight champion, and that's what we're building towards.
"Yes, he's more than welcome, but the difference is – when Klitschko came over to watch me in Manchester, we had signed a deal. It was signed and sealed, provided I won.
"With Wilder, I'm just not into the hype. If he wants to come over, get in the ring and all that stuff – I just prefer it if he had a fight in place to talk about, because if not, it's just hype."
Negotiations for a Joshua-Wilder fight have faltered due to differing opinions about the overall purse split.
But Joshua revealed that he has been in contact with Wilder's camp since last year and is confident they can reach an agreement.
"No-one wants to hear about – this percentage, who is ring walking first," said Joshua.
"They just want to know that we're going to fight. They don't care about the business and all that stuff that goes on in the background.
"That's why I don't want to get into the ring and turn it into a hype job. I want to give the fans what they want.
"I have been in touch with their camp since last December after I fought [Carlos] Takam, and it's something that we have been working on slowly, and we'll get there for sure."