The information -- protected for 80 years -- is expected to reveal Mayan beliefs in future catastrophes and wisdom characterized as "shocking,"
The end of the Mayan calendar in December 2012 has long given rise to theories and speculation about the end of the world.
The agreement will allow Julia-Levy to film in never-before-seen locations.
"The Mayans used to construct one pyramid over another," tourism minister for the Mexican state of Campeche Luis Augusto Garcia Rosado . "In the site at Calakmul workers for INAH [the National Institute of Anthropology and History] have discovered rooms inside the pyramid that have never been seen or explored before.
"And we're letting this documentary film there, to see what has been discovered inside the pyramid."
Julia-Levy said he'd been made aware of the secret Mayan information by former Mexican president Vicente Fox -- a friend of his family -- and that it took four years of phone calls to finally get the OK from current president Felipe Calderon.
"This is very important for humanity, not just for Mexico," said Julia-Levy. "This information has been protected for 80 years, and now it's important for people to understand the series of events that are coming, and the consequences for all of us."
The English-language documentary will be directed by Juan Carlos Ruflo (whose other films include the 2006 Sundance winner "In the Pit"), and will begin shooting later this year. Elbert said the filmmakers are talking to investors and waiting for the government to give them their first look at the material and the site.
One big condition from the Mexican government was that the film get an initial theatrical release, which is planned for next fall, said Ed Elbert who is co-producing along with Julia-Levy and Sheila M. McCarthy and executive producer Eduardo Vertiz.
"It has to be released before the end of the Mayan calendar, which is Dec. 21, 2012," said Julia-Levy.
That's the date that the Mayan calendar -- which some believe predicts a worldwide cataclysm -- comes to the end of a 5,126-year cycle, and resets for another cycle.
Julia-Levy has been specifically ordered not to talk about any of the more mystical possibilities that might strain credulity as Mexico prepares to launch the far-reaching (and tourism-inducing) 2012 Mayan World Program.
At one point, Rosado was quoted in a press release talking about contact between the Mayans and extraterrestrials. That statement has been recalled, and Rosado now paints this as a simpler, more archaeological-oriented documentary.
"At the moment, talk of the Mayans is a big thing," Rosado said. "We've counted over 3 million websites talking about the end of the Mayan calendar, and we have been contacted by a lot of producers who want to come and film on our sites."
The project is similar in some ways to a novel Julia-Levy was writing, variously entitled "Chronicles of the Mayan Tunnel" and "Secrets of the Mayan Time Machine." He and co-producer Elbert were also going to make a 3D movie from that novel starring him and Wesley Snipes, he said in the summer of 2010.
Several reports from that time said the novel was being written with the help of "secret information" never before released by the Mexican government. But in their conversations with TheWrap, Julia-Levy and Elbert dismissed that project as a "Harry Potter"-style piece of fiction with no connection to the current documentary.
That film has been set aside, they said, because Snipes is serving a prison sentence for tax evasion. "We put that film on hold," said Elbert. "Dollar-wise, this documentary might be smaller, but it is based on the release of new and important knowledge from the Mayans."
Asked if the movie will involve aliens, mystical elements or doomsday scenarios that have fueled the popular imagination, Julia-Levy declined to elaborate.
"I'm not allowed to speak about that," he said. "Everything is going to come out in time, but I can't comment on aliens or on 2012.
"I can just say that the Mexican government is preparing to tell humanity and the world things that are critical for us, for the way we live, for the way we've been handling the planet."
NEW MAYAN ARTIFACTS ARE REVEALED