The "Sorry" singer then got down on one knee in front of the whole crowd and popped the question and she accepted his proposal.
Representatives for Justin, 24, and 21-year-old Hailey, the daughter of actor Stephen Baldwin, have yet to comment on the claims, but Bieber's parents have since hinted the news is true in separate posts on social media on Sunday.
Justin and Hailey - who were linked in 2015 and 2016 - only went public with their rekindled romance in June. "Excited for the next chapter!"
"Love Love Love Love Love Love Love", Bieber's mother Pattie Mallette wrote.
Justin and Hailey have been nearly inseparable since they began dating about a month ago. "Justin has been extremely happy these past few weeks", a source told PEOPLE exclusively of the whirlwind engagement.
Justin Bieber and Hailey Baldwin - here in NYC last month - are reportedly engaged.
"Justin made arrangements for the ring when they were in NYC and knew that he wanted to propose to her".
In May she told the UK's "The Times" that she and Bieber, who both attend Hillsong Church in Los Angeles, had a tense time after their 2016 breakup.
Baldwin and Bieber have been together for one month, but have had an on and off again relationship for almost four years.
'I met him when I was really young and he was one of my best friends. We went through a long period of time when we weren't friends.