HARRY Potter and the Deathly Hallows: Part 2 has passed the $1b mark at the worldwide box office, distributor Warner Bros has said. The final instalment in the eight-part boy wizard series is the first to reach the milestone. Harry Potter and the Philosophers Stone had the previous best global takings with $974.8m in 2001. The 2009 epic Avatar holds the current record for the biggest worldwide box office haul with $2.8bn. Deathly Hallows: Part 2 is expected to pass Pirates of the Caribbean: On Stranger Tides soon, which is this years top grossing movie so far at $1.03b. The Harry Potter film took $21.9m at the North American box office over the weekend, climbing to a domestic total of $318.5m. It has now topped the franchises previous best in the US and Canada of $317.6m (193.6m) for Philosophers Stone. But taking into account todays higher admission prices, Deathly Hallows: Part 2 has not yet caught up to Philosophers Stone in terms of actual tickets sold. Meanwhile, The Smurfs and sci-fi western Cowboys and Aliens tied for the number one spot at the North American box office, both taking $36.2m according to early estimates. Definitive figures will be released later on Monday. In all my years, Ive never really seen a race this close, said Paul Dergarabedian of box office analysts Hollywood.com. Generally, in the world of movie box office, $1 million is a close call, so to have two films in a dollar-to-dollar tie is somewhat unprecedented. BBC