Brook was linked to facing huge names in Amir Khan and Timothy Bradley before eventually being forced to settle for lesser-known Argentinian Diego Chaves for his next IBF title defense and Witter says more US appearances are needed.
Arch-rival Khan has enhanced his name considerably worldwide with a string of high-profile opponents on US soil and is currently way ahead of Brook in the popularity stakes across the Atlantic.
An August 2014 victory over Shawn Porter is the best win of only two American outings for Brook through 35 bouts and Witter says those huge events and unifications craved may elude ‘The Special One’ if he continues to fight in the UK.
“If he wants Khan or Bradley, Kell has got to go to America,” Witter told World Boxing News in a ringside interview over the weekend.
“I understand why he wants to be at home, but if he wants those big fights then he has to go to America.
“Fighters like Bradley don’t want to come to the UK anymore. I know he came in the past, but now it’s a different story.
“I think they (Matchroom) want to keep him in Sheffield at home, but he has to go to America. I don’t even think he’ll get Khan if he doesn’t at least go over there to raise his profile.”
On Brook v Chaves, which takes place on October 24 in Sheffield, Witter predicted a tough night for his fellow Yorkshireman.
“I think Chaves is a lot harder fight for Kell than people are saying,” he said. “Chaves is going to be rough and make it a hard fight for Kell however long it lasts.”
Witter himself is hoping for a return later in the year following his shocking points defeat to Ahmed El Mousaoui in France when ‘The Hitter’ lost out on the EU title even though it looked as if he’d done more than enough to win.