Michael Moore is back with another provocative documentary.

In Where To Invade Next, the Oscar-winning filmmaker and political activist apparently tells the Pentagon to stand down so he can take over the job of invading other countries.

It's another inflammatory topic - the relationship between the United States and its enemies - for the controversial director of such films as Bowling for Columbine (on gun control), Fahrenheit 9/11 (on George Bush's war on terror), Sicko (on American health care) and Capitalism: A Love Story (on the US financial crisis).

Moore calls it "a film of epic nature."

The documentary will have its world premiere at the Toronto International Film Festival in October then screen at the New York Film Festival, which has described it as looking at America from the outside this time around.

"Where To Invade Next is provocative, very funny, and impassioned," the festival's screening notes say. "But it's also pretty surprising."

While Moore has kept the content secret, including the places apparently invaded, he has started to reveal the odd detail.

One clue came in in a Q&A session on the live video streaming app Periscope about whether there was a particular trigger for the film or whether it came from a sense of the US being "at infinite war".

Moore said that "the issue of the United States at infinite war is something that has concerned me for quite some time and provides the necessary satire for this film."

But rather than a particular trigger, Where To Invade Next reflected what has been happening in the US since the September 11, 2001, terrorist attacks.

"It's the constant need, it seems, to always have an enemy - where's the next enemy? - so we can keep our whole military industrial complex alive and keep the companies that make a lot of money from this in business.

"I've always been a little bothered by that so that's where the comedy comes from."

On whether his documentaries should be be more about entertainment or social content, Moore said he aimed for both.

"The first thing I tell the crew on day one is we're not making a documentary, we're making a movie," he said.

"Documentary or non-fiction is just the vehicle we're using. You can tell a good story with fiction, you can tell a good story with non-fiction.

"We choose non-fiction but it's a movie because I'm asking you to give up your Friday or Saturday night and come to the theatre and buy a ticket and $9 popcorn ... I want you to have the best cinematic experience that you could possibly have going to the movies."

In a second Periscope Q&A, Moore revealed he filmed on three continents.

"I think you'll enjoy where I took my army to invade," he said. "And hopefully appreciate it too at the same time"

Moore took a swipe at US presidential candidates Jeb Bush, brother of former president George W. Bush, and, more surprisingly, Hillary Clinton.

"I think this is going to be a very fun election year," he said. "I don't know if that's good for the country, it being fun.

"But at least funny. Maybe that's a better way to put it."

On Bush, he was dismissive: "Enough said, please. Enough of that."

He had mixed feelings about Clinton.

"I wrote a chapter in my first book back in the nineties called My Forbidden Love for Hilary." he said. "The love has waned and grown and then waned again."

But there was one issue Moore believes the presidential candidates need to address - black lives mattering.

"All white liberals should maybe think about that a little bit," he said. "There are so many things that we have to deal with in this country especially when it comes to race.

"People shouldn't be afraid fo it. It's absolutely encumbent on everyone, especially white people, to help put an end to this once and for all."