Liv Tyler and Viggo Mortensen have topped a new list of Hollywood's highest earning on-screen couples thanks to their Lord Of The Rings romance.

The pair's Middle Earth lovers, Aragorn and Arwen, helped director Peter Jackson rake in $2.9 billion at the worldwide box office - making them the top-earning Hollywood couple, according to a new Forbes magazine list of duos who have appeared in at least two films together in the last 20 years.

Tobey Maguire and Kirsten Dunst's onscreen chemistry in the Spider-Man franchise pulled in $2.5 billion, while Leonardo DiCaprio and Kate Winslet's doomed relationships in 1997's Titanic and Revolutionary Road in 2008 earned a combined $1.9 billion.

Meanwhile, Shia LaBeouf and Megan Fox's adventurous affair in the two Transformers blockbusters took in $1.5 billion.

But Forbes editors predict the fourth place entry - Twilight lovers Robert Pattinson and Kristen Stewart - will have the most bite when the vampire franchise is completed.

Pattinson and Stewart's passionate relationship in the first two installments of the franchise has already grossed $1.1 - and two "Twilight" follow-ups have yet to hit cinemas.

George Clooney and Julia Roberts' flirtatious pairing in Ocean's Eleven and Ocean's Twelve rounds out the top five couples with $847 million.

Sam Worthington's romance with Zoe Saldana in the world's biggest-grossing film of all time, Avatar, was ineligible for the list because the duo has only starred in one film together.

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