The music mogul and X Factor judge - who manage 1D - talked about the global boy band in a new interview with Billboard.
The boys - Liam Payne, Harry Styles, Louis Tomlinson and Niall Horan - announced their hiatus last year and are now taking a well-deserved break from group commitments.
There's been no official word on when they'll be back, but they have promised in several interviews that they will return. However, Simon has now admitted that even he is unsure.
"I don't know if it's a hiatus or a breakup, to be honest," Simon said. "In a weird way, I don't want to know. I don't think they've had enough time to experience what it's like not being in the group to really answer that."
Simon said the boys had talked to him on several occasions about taking a break.
"Whenever I was with them, we talked about it, and I couldn't argue with them," he said. "They had achieved so much in a short period of time, and I didn't want them to get jaded."
Simon also talked about Harry, who recently bagged himself a role in Christopher Nolan's new thriller Dunkirk alongside Tom Hardy.
With a film on the horizon, Simon also hinted that Harry will pursue a solo career after being inundated with offers.
Simon added: "He'll work out what kind of record he wants to make because he's got great taste which is always a help. All the writers and producers want to work with him, understandably, but he probably won't rush into it."
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