The Northern Territory’s push to become Australia’s seventh state could see our national flag changed, Prime Minister Tony Abbott says.

A communique from the Council of Australian Government’s retreat in Sydney revealed state leaders unanimously supported the idea of Darwin becoming a state capital by July 1, 2018.

Australia’s flag features the Southern Cross alongside the seven-pointed Commonwealth Star, which represents the six states and all future territories of Australia.

The seventh point was added in 1909 after the Australia claimed the Territory of Papua four years earlier.

Would you support changing the Australian flag if the Northern Territory is granted statehood? Yes 7922 No 3815

Speaking in Sydney today, the confusion over our flag appeared to even get the better of Mr Abbott.

"I'm not in favour of changing the flag, I've got to say, although I have to say that the Commonwealth star was to be a seven-pointer star rather than a six-pointer star, that's hardly a massive change," Mr Abbott said – apparently forgetting we already have seven points on the Commonwealth star.

"I would say that is an evolution rather than a revolution.”

Should the Northern Territory gain statehood, the House of Representatives and Senate could gain more seats and the territory may need to be renamed.

NT Chief Minister Adam Giles thanked his federal and state counterparts for backing the push for statehood.

"With second tier status in the nation ... I was very pleased to have support from colleagues," he said at the COAG meeting today.

The flag of the Northern Territory. (Supplied) (Supplied)

Despite a number of previous efforts from various parties to push for NT statehood, Territorians themselves voted against it in a 1998 referendum.

Do you think the Northern Territory should become a state? Yes 21026 No 9078