The Barcelona defender spent four years at Old Trafford, between 2004 and 2008, and was heavily linked with a switch to City in 2016 after Pep Guardiola was appointed at the Etihad.
But the former Red Devil went on record saying he would never sign for the Blues. “My love for Manchester United is too big to let me even consider signing for City one day, even with Guardiola in charge," he said.
Pique's comments have resurfaced after it was revealed that City were considering making a move for Cristiano Ronaldo, who is in the final year of his contract at Juventus. According to Sky in Italy, Guardiola's side are willing to offer the five-time Ballon d'Or winner a two-year contract worth £12.8 million a season.
In the past, Ronaldo, who scored 118 goals in 292 games for United, played down a move to the club's local rivals in an interview with the BBC in 2015.
"You think the money is going to change my mind now?" he said.
"I don't think so. I think it is not going to be the problem, because if you will speak about the money, I will go to Qatar. [They] maybe have more money than Manchester City, but it's not about the money. It's about the passion."