The 21-year-old has ended his 14-year association with the Reds by linking up with the Hatters during their first-ever Premier League season.
Having joined United as a seven-year-old, Teden rose through our Academy system and has represented the club in every age group including the senior team.
Mengi featured predominantly for our Under-21s last season, turning out seven times in our Premier League 2 and EFL Trophy campaigns.
He made his debut for our men's team against LASK Linz in the Europa League back in 2020, appearing as a late substitute in our 2-1 victory at Old Trafford.