The television presenter was making her way to a breakfast meeting at London's Ivy restaurant when the accident happened, her agent Jonathan Shalit confirmed.
"Myleene stopped at a red light and the lorry behind her hit her. She pulled over expecting the driver to swap details, but he took one look at her, jumped back into his cab and drove off," ThisIsCroydon quotes him as saying.
"Perhaps it was because he recognised her or because of the damage - there's at least £2,000 worth of repairs."
Klass's agent added that she had been shocked by the incident but carried on with her day's schedule.
"She was very shaken, but she's a trouper and didn't want to let anyone down," he added.