The ambitious Avengers film has exceeded box-office expectations (Marvel Studios)

The Avengers film looks set to be one of the highest grossing of all time after smashing box office records in the United States and making more than $1bn worldwide.

The Joss Whedon directed superhero blockbuster exceeded the expectations of its own studio with huge takings on its first two weekends in the US, bringing in $207m (£128m) and $103m - both record takings.

The US sales joined record-breaking openings in dozens of countries to see the film's gross takings exceed $1bn, with many weeks of showings remaining.

Avengers smashed the second weekend record set by James Cameron's Avatar, which took $75.6m, putting the star-studded comic book adaptation on course to be one of, if not the, biggest hits at the worldwide box office.

The film represented a high-concept gamble for Disney-owned Marvel Studios. It was the first sequel to create its own ensemble through a series of films based on its main characters.

The Avengers brought together the stars of Captain America, Thor, Iron Man and The Incredible Hulk, with only one cast change as Mark Ruffalo replaced Edward Norton as Bruce Banner.

The Hulk
Mark Ruffalo starred as Bruce Banner and The Hulk (Marvel Studios) Marvel Studios

Films such as Captain America and Thor represented a major gamble, each representing tough sell to those unfamiliar with their comic book roots.

However, it seemed the pull of the Avengers project itself helped bolster audiences, with Captain America taking $192m and Thor $268m. Both of these total takings have been shattered by the Avengers within two weeks.

The success of the film led to Whedon writing a letter online to thank his fans for their support of the project.

Writing on comicbookmovie.com, Whedon tells his fans about how the Avengers's huge takings will change his life:

"What doesn't change is anything that matters. What doesn't change is that I've had the smartest, most loyal, most passionate, most articulate group of - I'm not even going to say fans. I'm going with 'peeps' - that any cult oddity such as myself could have dreamt of," he wrote.

In an interview with SFX, Whedon said that the Avengers sequel, hinted at by a post-credit glimpse of an iconic villain, would be a "smaller" film.

When asked how the second film could ever be bigger than the first, he said: "By not trying to. By being smaller, more personal, more painful. By being the next thing that should happen to these characters, and not just a rehash of what seemed to work the first time. By having a theme that is completely fresh and organic to itself."