“We hadn’t seen each other in those 20 years,” Lachey said.

• Nick Lachey has revealed what really happened when he ran into ex-wife Jessica Simpson on a recent six-hour flight to Hawaii.

• “It’s been 20 years since we’ve been [together], and we hadn’t seen each other in those 20 years,” Lachey said on Watch What Happens Live.

• Lachey said he was with his wife Vanessa Lachey and Simpson was with her family.

98 Degrees pop star Nick Lachey has opened up about what really happened when he encountered his ex-wife, recording artist, and his Newlyweds: Nick and Jessica costar Jessica Simpson on a recent flight to Hawaii.

The singer fielded a question Wednesday from host Andy Cohen on Watch What Happens Live about the reported run-in, which made headlines in April.