The 37-year-old actor confessed in an interview with The Breakfast Show with Nick Grimshaw on BBC Radio 1 that Dewan "broke down crying" after he tried to mislead her before popping the question.
"When I proposed to my wife I did something pretty cruel because I thought she was onto me," Tatum told host Nick Grimshaw. "I basically told her I never wanted to get married to try to throw her off."
"I told her, 'I don't believe in the institution of marriage and I don't think I ever want to get married,'" he recounted.
"She basically broke down crying. I thought, 'This is not going well at all,' so I had to propose to her sooner than later."
People reported Tatum ultimately proposed to Dewan in front of their close friends during a trip to Maui, Hawaii.
The couple, who met on the set of the movie "Step Up," married in July 2009, and welcomed daughter Everly in May 2013.
"We actually showed [Everly] 'Step Up' for the first time," Tatum told "Jimmy Kimmel Live!" this month. "Within 10 seconds, she was like, 'Can I watch a real movie? Like, a good one?'"
"We were like, 'What do you mean? This is a real movie!'" he recalled. "And, like, 10 more seconds went by and she was like, 'Please, can I watch a real movie?' And were like, 'Fine, just put on 'Moana.''"
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