The 19-year-old heart throb ''can't stand'' being separated from dancer-and-model Danielle Peazer and admitted he would ditch the boy band to save their relationship.
He said: ''I can't stand being away from Danielle. If it's between the band and her, I'll choose her.''
According to the Daily Star newspaper, Liam wanted to bring his girlfriend with him as the quintet embark on a four-month stint in the US, but record label bosses want One Direction to work as a team without any distractions.
A source told the publication the singer gets homesick, and his relationship with Danielle is the deal-breaker - particularly after their original split in September because of his band commitments.
The insider said: ''They split up in the first place because they were apart for so long when he was on tour.
''So Liam is terrified the same problems will creep in when the real hard slog of touring the world starts again soon.
''He wants Danielle with him but the other lads and the record company think they should be concentrating on work.''
They added Liam relies on Danielle for ''emotional support'', preferring stability to the partying fame game.
The source continued: ''Since getting back together with Danielle at the end of last year they have grown much closer and really bonded. Liam hates being away from her.
''He relies on her for so much emotional support. Some of the other lads in the group are the total opposite - they just want to party and chat up girls.''
The star reportedly questions whether the band is right for him, with the rest of the group worrying he'll ''throw the band into chaos'' by leaving.
The insider revealed: ''Liam feels he doesn't get the same status and respect as the big stars like Harry [Styles] and Niall [Horan] and sometimes even questions why he's in the band at all.
''The rest of the lads are freaking out that one day he'll have had enough and just walk out. That would throw the whole band into chaos.''
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