Phillips says the rivalry between his former club Leeds United and the Old Trafford outfit would never have allowed such a union to happen.
The England international however opted to move to the Blue half of Manchester, signing a six-year deal with Premier League champions City for £45m.
Phillips came through the Leeds United youth ranks and was instrumental in their promotion to the Premier League for the first time in 16 years in 2020.
Phillips made 235 appearances for Leeds after breaking into the first team.
Asked if there was ever a possibility he was going to end up at United, Phillips said: ‘No, there was never any chance of me going there. You know my loyalty to Leeds, my family as well, they’re all Leeds fans.
‘I was honoured by United wanting me, such a big team – one of the biggest teams in the world. But no, I had to stay loyal to Leeds and choose to go to the other side of Manchester.’
Asked if his stance was somewhat unusual in modern football, Phillips added: ‘I don’t know, it’s just the way I am, the way I think and the way I’ll always be.
‘I want to be loyal to the people who’ve given me the biggest opportunity in the world. Leeds were the first team to sign me, I made sure that was one of the main things I’d do.’
‘It was the opportunity to be coached by Pep even if it’s just for a year or hopefully longer,’ Phillips said.
‘I know he’s a great manager and he’ll elevate my game to a level I want to be at, and be involved in teams fighting for trophies.
‘Also just be around players that make you a better player every single day. The opportunity I was given was one I couldn’t turn down.’
