Ashlee Simpson and actor Vincent Piazza have gone public with their romance after attending a Boardwalk Empire season premiere together on Wednesday.

Simpson was snapped kissing and walking arm-in-arm with the actor in New York City in June, sending gossips into a flurry, and the Pieces of Me singer was all smiles as she joined Piazza on the red carpet for their first public appearance.

She was supporting him as he celebrated the launch of his hit TV show's second season.

Simpson filed for divorce from her husband, Fall Out Boy rocker Pete Wentz, in February.