The reality TV star and singer is good friends with the band - which consists of J.B. Gill, Marvin Humes, Aston Merrygold and Oritse Williams - and is upset they have decided to call it a day following the release of their greatest hits album 'Goodbye' and a farewell tour in December.
Writing in his new! magazine column, he said: ''I'm sad that JLS have split up, but I can understand why they wanted to go out on a high.
''I'm good mates with all the lads from JLS and want to wish them the best of luck. Marvin Humes even invited me to his and Rochelle's wedding last year, but I couldn't go. I was gutted!''
The 40-year-old star believes he and Oritse will become even better friends now he has signed up with his manager Claire Powell.
Peter added: ''Oritse Williams is now being managed by Claire Powell, who manages me, and I know she's got lots of exciting stuff lined up for him. Being under the same management means we'll probably get to hang out lots, which I'm looking forward to.''
The 'Everybody in Love' hitmakers announced their split last week after finding fame on 'The X Factor' in 2008.
Marvin said: ''We never wanted to overstay our welcome. We never wanted to be that band where people said, 'Oh, bloody hell. It's JLS again.' We wanted to finish on a high. We're finishing with an arena tour - our third arena tour - and that is a massive achievement.''