The Dark Knight Rises stayed atop the US box office for the second straight weekend, making just over $US64 million ($A61 million). But it's lagging behind the staggering numbers of its 2008 predecessor, The Dark Knight.

The final piece in Christopher Nolan's Batman trilogy has now grossed more than $US289 million in its first 10 days in theatres. It dropped 60 per cent from its opening weekend of $US160.9 million.

By comparison, The Dark Knight took a 53 per cent drop in its second weekend with a gross of nearly $US75.2 million and a 10-day cumulative gross of $US313.8 million.

Dan Fellman, head of distribution for Warner Bros, declined to comment on the Sunday estimates again out of respect for the victims of the Aurora, Colorado shooting that left 12 people dead and another 58 injured at a midnight showing of the film on opening night.

But people are still going to the movies, and they did so even last weekend, said Hollywood.com analyst Paul Dergarabedian. If anything hurt the numbers for all movies this weekend, he said, it was Friday night's opening ceremony of the 2012 Olympics in London, which drew a record 40.7 million viewers in the United States.

'For a film that opened as big as this did, considering the situation and what happened last weekend and all that, I would say this is a very strong showing,' Dergarabedian said.

'It's made almost $US300 million in North America and its mid-week (attendance) is very strong. It made $US19 million last Monday.'

In second place this weekend was the animated family film Ice Age: Continental Drift, which is still going strong in its third week. It made $US13.3 million for a domestic total of nearly $US114.9 million. The fourth movie in the 20th Century Fox franchise features the voices of Ray Romano, Denis Leary and Queen Latifah.

Both of the new movies in wide release opened weakly.

The Watch came in third place with $US13 million. Big-name comic actors Ben Stiller, Vince Vaughn and Jonah Hill play a group of guys who come together to form a neighbourhood watch; despite the star power, the film was panned critically.

And Step Up Revolution - the fourth film in the dance franchise, which is set in Miami this time - opened at number four with $US11.8 million.

Estimated ticket sales for Friday through Sunday at US and Canadian theatres, according to Hollywood.com.

1. The Dark Knight Rises, $US64 million. ($US122.1 million international.)

2. Ice Age: Continental Drift, $US13 million. ($US49.4 million international.)

3. The Watch, $US13 million.

4. Step Up Revolution, $US11.8 million. ($US5.2 million international.)

5. Ted, $US7.4 million. ($US2.7 million international.)

6. The Amazing Spider-Man, $US6.8 million.

7. Brave, $US4.2 million. ($US9.6 million international.)

8. Magic Mike, $US2.6 million. ($US5.3 million international.)

9. Savages, $US1.8 million. ($US2 million international.)

10. Moonrise Kingdom, $US1.4 million.