The Mexican fighter shocked the boxing world last weekend, after dropping Joshua four times, before stopping him in the seventh round.
The Brit immediately triggered the rematch clause, with the second fight due to take place in November or December.
Ruiz is likely to pick up £10m for the rematch, double his purse for his first clash with Joshua, but he is ready to demand more.
“Right now my team, they’re negotiating everything right now. I’ve just got to stay busy, stay healthy and be ready for the rematch.
“I’d love it to be here in the United States or in Mexico you know. It all depends on the team and what they negotiate.
“If they want me to go over there, they’ve got to give me $50million. If they want to come over here… It’s just negotiations you know,” he told Fight Hub.
