Whyte had been a potential to step in against Anthony Joshua, who will fight at Madison Square Garden on June 1.
It comes after Jarrell Miller failed a drugs test and was banned from fighting.
But Whyte will not head to New York with his next fight coming against Oscar Rivas at the O2 on July 20.
“I am very happy to be fighting again at The O2 in July,” said Whyte.
“Oscar Rivas is undefeated and ranked in the top 10 across the board of all the governing bodies.
“He has been one of the most avoided heavyweight fighters in the last few years.
“His KO victory over Bryant Jennings sent shockwaves through the division and Tyson Fury just turned down ESPN/Top Rank’s offer to fight him.
“I am over the moon that he has accepted the fight. He has a great amateur and professional record, including a win over Kubrat Pulev.
“I am more than happy to carry on fighting top 10 fighters like Rivas until I get my well-earned shot at Deontay Wilder or Anthony Joshua.
“I can’t wait until July 20 to fight again at The O2 which is one of the best venues in the world for boxing.”
“I have waited for this opportunity for a very long time,” said Rivas.
“Dillian Whyte is an excellent boxer, a World class fighter and the number one contender.
Rivas is unbeaten from his 26 fights and beat Kubrat Pulev as an amateur in the 2008 Olympic Games.
“He deserve all my respect for his accomplishments and I am grateful for the opportunity he is giving me.
“This is exactly the kind of challenge I was hoping to get. I am undefeated, I am planning to keep my perfect record after July 20 in my quest to get the ultimate opportunity to become world champion.”