Washington, July 21 (DPA) It's been decades since they set foot on the moon, but the pioneers of the Apollo programme remain committed to exploring space with the goal of sending a human to Mars.

Seven astronauts from the Apollo programme talked with journalists Monday to mark the 40th anniversary of the Apollo 11 landing on the moon. Events later would include a celebration at the National Air and Space Museum and a meeting at the White House.

Many of the retired astronauts, now in their 70s and 80s, said they were disappointed that NASA has not returned to the moon and ventured even further afield to Mars.

'I don't think there was a soul in the astronaut office back in the 1960s that wouldn't have thought we'd be on (Mars) by the year 2000,' said Walt Cunningham, the pilot of Apollo 7.

But achieving that goal will take a commitment by the US government and must go beyond the current goal of returning to the moon by 2020.