The teenager left the West Midlands outfit to join Borussia Dortmund in 2020, and has enjoyed a meteoric rise since, earning both the captaincy of the Bundesliga club and full England honours.
After a series of strong FIFA World Cup performances, Bellingham is now tipped to head to a major European rival next year, with Liverpool and Real Madrid both linked with his signature.
But former Birmingham chief has revealed United previously made an aggressive pursuit of the 19-year-old when he was in the English lower leagues, ultimately coming up short with a package to persuade its target.
"[Former managing director] Ed Woodward was the one who was most insistent," Xuandong Ren told Mundo Deportivo. "We sat down and talked about how we could convince Bellingham.
"Manchester United offered twice as much as the rest of the clubs [chasing him]. They even brought him together with [former manager Alex] Ferguson, [Eric] Cantona and [Ole Gunnar] Solskjaer.
"But Jude did not make any decision based on money. They were offering much more salary compared to the rest, maybe double. He was going to be guaranteed millions in the bank and he didn't take it.
"That's not normal for a player. It was a difficult position, because I wanted to respect his decision. Our promise was that we would let him make the decision because of the loyalty he showed us."