She and Asghari posed for photos. Britney was later spotted being escorted back into her car, a source told "eonline.com".
The singer has mostly stayed out of the spotlight in last few months amid personal and legal turmoil involving her and her family. She last appeared at a red carpet event in July, when she and Asghari attended the premiere of "Once Upon a Time...in Hollywood" here.
Recently, a hearing was held to discuss the status of her conservatorship. Her 67-year-old father, Jamie Spears, had mostly controlled her financial and medical affairs since her 2007 public meltdown. The case remains pending.
Earlier this month, her ex-husband Kevin Federline filed a criminal complaint and obtained a restraining order against Jamie, which bans him from contact with the former couple's two sons, after accusing him of getting physical with one of them.
Prosecutors later announced they will not proceed with an investigation, citing "insufficient proof that a criminal offense was committed by Mr. Spears".
Days after Kevin's restraining order was filed, Jamie asked a judge to temporarily relinquish his powers of conservatorship over Britney, citing "personal health reasons". He had had a physical health scare last year, promoting Britney to cancel her shows and announce an indefinite work hiatus in January.
The singer also underwent treatment at a mental health facility.