Australian political leaders Thursday backed the establishment of the country's seventh state - the Northern Territory - by mid-2018, with Prime Minister Tony Abbott conceding the national flag could be changed.

The push for the Northern Territory, which has a population of 244,000 but covers a vast area, to be a state was initiated by Chief Minister Adam Giles who said it should not be a "second-class citizen" in Australia.

"When we come together and talk about federation, it would be remiss of me not to raise the issue of the Northern Territory being a second-class citizen, with second-tier status in the nation," Giles said.

"So I was very pleased to have support from colleagues at the table that I'm at now to see the Northern Territory strive to become a state by 1 July, 2018," he noted after a meeting of Australia's six state and two mainland territory leaders with Abbott.

Unlike the six states - New South Wales, Queensland, South Australia, Tasmania, Victoria and Western Australia - the country's two mainland territories, the Northern Territory and the Australian Capital Territory, have a limited right of self-government.

Seven other territories, including the Australian Antarctic Territory and Christmas Island, are governed only by federal laws.

Abbott said he was not in favor of changing the national flag, which features a miniature version of the Union Jack along with an array of stars, but was not against any alterations either.

"[If] the Commonwealth star was to be a seven-pointed star rather than a six-pointed star, that's hardly a massive change," the Australian leader said at a news conference.

"I would say that that is an evolution rather than a revolution. But, look, we all acknowledge that this is a very long-standing aspiration on the part of the Territory ... and we are prepared to work with the Territory to see how it can be done."

An additional point for the prospective northern state would actually give the Commonwealth star eight points rather than seven.