JOIN USLocal organisers said they expected a 100,000 strong crowd for Sunday's inaugural race, with enough seating in place for 10,000 more.
“Considering what it was and what they've had to do, and it's not been easy to do this event, I think they've done a good job,” the 79-year-old Ecclestone told reporters on a visit to the circuit media centre.
“It's all there. If there hadn't have been all the bad weather then it would have been done a long time ago,” the F1 supremo said.
The race, 17th of 19 this season, had looked in doubt only a few weeks ago with the final layer of asphalt still to be laid and an official inspection by the governing International Automobile Federation (FIA) repeatedly postponed.
“I wasn't worried because I had some information from upstairs that they would get it done, and they've got it done,” said Ecclestone. “It would have been bad for Korea if it didn't happen, so they have made sure it happened.