LOS ANGELES - In an unprecedented display of strength, "Avatar" led the worldwide box office for a fifth consecutive weekend, fast catching up on all-time champ "Titanic," distributor 20th Century Fox said on Sunday.

James Cameron's sci-fi spectacular has now earned $1.6 billion, just $237 million short of the $1.8 billion record set by the filmmaker's "Titanic" in 1998.

"Titanic was a ship. Avatar's a rocket ship," said Chris Aronson, Fox's senior vice-president of domestic distribution.

The North American contribution stands at $491.8 million -- the third-highest tally of all time -- thanks to a $41.3 million weekend. Fox, a unit of News Corp, expects it to hit $500 million on Monday, when business will get a boost from the U.S. Martin Luther King holiday.

That will mark the film's 32nd day of release. By contrast, "Titanic" took 98 days to reach that tally on its way to a record $601 million. On the other hand, "Avatar" sales are inflated by higher ticket prices in general and premium pricing for 3-D screenings.

Aronson said he expected "Avatar" to surpass the $533 million haul of 2008's "The Dark Knight" next weekend, leaving only "Titanic" ahead of it. The No. 3 slot was previously held by "Star Wars" with $461 million.

Aronson said the $600 million level is "within our sights," and he predicted the February 2 announcement of the Academy Award nominations to pique interest.

"AVATAR" AT $1.1 BILLION OVERSEAS

"Avatar" is enjoying strong holds every weekend. In the current period, it was off just 18 percent. "Titanic" was the last movie to lead the box office for five consecutive weekends, although "Avatar" might struggle to reach its record of 15 unbroken weekends.

The foreign total stands at $1.1 billion after a $125 million weekend. "Avatar" trails the "Titanic" overseas haul of $1.2 billion by just $127 million.

"Avatar" is the tale of a disabled ex-Marine sent from Earth to infiltrate a race of 10-foot (3-meter) blue aliens and persuade them to let his employer mine their homeland for natural resources. It was reportedly the most expensive film ever made, with a budget of at least $300 million.

Elsewhere in North America, Denzel Washington's "The Book of Eli" opened at No. 2 with $31.6 million, the actor's second-best opening after the $43 million launch of 2007's "American Gangster." Young men accounted for about two-thirds of the audience for the Christian-themed apocalyptic thriller, said distributor Warner Bros. Pictures.

The $80 million film was produced by FedEx Corp Chairman Fred Smith's Alcon Prods., and distributed for a fee by Warner's Time Warner Inc parent. Alcon principal Andrew Kosove said he expected the film to reach the mid-$80 million range, surpassing the breakeven point of $67 million after DVD and TV sales are factored in.

Director Peter Jackson's adaptation of "The Lovely Bones" took the No. 3 spot with $17.1 million in its first weekend of national release, as the "Twilight" crowd flocked to the supernatural murder story.

Distributor Paramount Pictures, a unit of Viacom Inc. said women accounted for almost three-quarters of the audience, and 40 percent of moviegoers were aged under 20.

The big-screen version of the Alice Sebold novel about a murdered girl had played in a total of three theaters in New York and Los Angeles for the past five weeks. Its total now stands at $17.5 million.

The only other major new release was Hong Kong action hero Jackie Chan's family comedy "The Spy Next Door," which opened at No. 6 with a modest $9.7 million. It was released by Lionsgate, a unit of Lions Gate Entertainment Corp.