Australia has seen a "huge growth of illicit and illegal tobacco" since plain cigarette packaging was introduced, a retail expert told Good Morning Britain.
Jeff Rogut, from the Australasian Association of Convenience Stores said there had been a "dramatic shift" towards cheaper brands as well as customers choosing to buy illegal cigarettes, which could contain more toxins than regular ones.
More top news
In an email to the actor, Twitter said the tweet “has the potential to be misleading in a way that could impact an election”.
The man was detained by security staff on Sunday evening.
The Duke of Sussex will make a speech at the Loughborough University event.