Iron Man 3 has triumphed at the US box office, with the second biggest ever opening weekend in the US.

Comic book sequel Iron Man 3, starring Robert Downey Jr., took an estimated $175.3 million across the weekend.

Only 2012’s The Avengers, which united Iron Man with fellow Marvel characters, had a bigger opening, taking $207.4 million when it opened last May.

Iron Man 3 is the final episode in the trilogy, and follows Tony Stark’s battle with terrorist “the Mandarin”.

Iron Man 3 has triumphed at the US box office, with the second biggest ever opening weekend

Directed by Shane Black, who previously worked with Robert Downey Jr. on Kiss Kiss Bang Bang, the film co-stars Gwyneth Paltrow, as Pepper Potts, and Sir Ben Kingsley as the Mandarin.

Iron Man 3, which has enjoyed largely positive reviews, has easily outstripped the opening weekends of the first two films, which took $98.6 million and $128.1 million respectively.

The film opened a week earlier overseas, taking $504.8 million at the international box office – meaning it has already grossed $680.1 million in total.

Robert Downey Jr. is expected to reunite with fellow comic book characters Captain America, Thor and the Hulk in the forthcoming Avengers sequel, which is scheduled to be released in 2015.

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