Preliminary planning is underway for the possibility of war with North Korea, even as the focus remains on finding a diplomatic resolution to Pyongyang’s refusal to give up its nuclear weapons and cease testing ballistic missiles, the nation’s top Marine told a Washington think tank Thursday.

“I think the biggest thing everybody’s done is just look at, get familiar with the geography, get familiar with the plans and do some logistical preparation that’s just prudent,” said Gen. Robert Neller, commandant of the Marine Corps, at the Center for Strategic and International Studies.

Neller credited U.S. Korea Commander Army Gen. Vincent Brooks and U.S. Pacific Commander Adm. Harry Harris with having “done a very good job” conducting training and rehearsing “force deployment options” in order to send a strong message to North Korean leader Kim Jong Un.

That message: “You don’t want to do this. You really don’t want to do this,” Neller said.

The plain-spoken Marine, who on a recent visit to Norway told Marines exercising there to be ready because there is a “big-ass fight” coming, said he wasn’t predicting war with North Korea, just trying to tell his Marines they need to be ready.

“I go out and talk to Marines. I try to break it down for them as simple as I can,” Neller said, admitting that in discussing the prospect of all-out war on the Korean Peninsula, he has compared it to the coming climactic battle in the fictional HBO fantasy series “Game of Thrones.”

“They haven’t started this year’s episodes of 'Game of Thrones,' so I really don’t know how it’s gonna turn out, other than the Army of the Dead has made it across, they have torn down the wall, and they got a dragon,” Neller said. “I mean I could come up with all sorts of analogies to that. So there’s a dragon over there, and I think we know what it is,” he said in an apparent reference to North Korea’s nuclear and missile capabilities.

“I wasn’t predicating. I wasn’t saying it was going to happen. I hope it doesn’t happen. I don’t want it to happen. It would not be good for anybody,” Neller said.

“I’m not trying to glorify this. I believe however it turns out it will be a very, very kinetic, physical, violent fight over some really, really tough ground and everybody is going to have to be mentally prepared,” he said. “I was trying to make sure the Marines understood, that when they train they have to keep in the back of their mind they have to be physically, mentally, and always their spirit has to be steeled for serious conflict that’s going to test them beyond anything they have ever done in their life.”

Neller's comments in Norway came up this month at a White House press conference when a journalist asked President Trump what Neller meant when he referred to a "big-ass fight."

“Maybe he knows something I don't know,” Trump said.

He added, “No, I don't expect that. I think we'll have, because of strength, peace through strength. I think we'll have a long period of peace. I hope we do.”

Neller on Thursday said he should have used more cautious language when he made his comments in Norway.

“The moral of that story is when you fly all night and you go to Norway and there’s only four hours of daylight, just be careful what you say.”