FOREIGN Minister Julie Bishop has spoken of the “grave” threat Australia faces from a nuclear-armed North Korea, as Australia hit back at the latest incendiary comments from the reclusive state.

After North Korea accused Australia of “blindly and zealously toeing the US line” and threatened a nuclear strike on one of America’s chief allies in the Pacific region, Ms Bishop said the country’s military ambitions could not continue to go unchecked.

“North Korea’s threats of nuclear strikes against other nations further underlines the need for the regime to abandon its illegal nuclear weapons and ballistic missile programs,” she said.

“These present a grave threat to its neighbours, and if left unchecked, to the broader region including Australia.

“The North Korean government should invest in the welfare of its long-suffering citizens, rather than weapons of mass destruction.”

North Korea’s threat of a nuclear strike on Australia is of “enormous concern” but such threats have become part of the regime’s day-to-day rhetoric, according to the Opposition.

The rogue state turned its sights on Australia, threatening nuclear retaliation after Foreign Minister Julie Bishop said North Korea would be subject to further Australian sanctions.

North Korea’s state-run KCNA news agency quoted a foreign ministry spokesman accusing the Australian foreign minister of “spouting a string of rubbish against the DPRK over its entirely just steps for self-defence”.

“If Australia persists in following the US moves to isolate and stifle the DPRK and remains a shock brigade of the US master, this will be a suicidal act of coming within the range of the nuclear strike of the strategic force of the DPRK.

Labor’s defence spokesman Richard Marles today said North Korea’s statement was a matter of enormous concern, but noted Pyongyang had made similar threats to other nations, even a veiled one at China.

But Marles did not believe conflict on the Korean peninsula was particularly likely and backed the approach the US has taken on North Korea.

“I do think a harder edge being presented by America in respect of North Korea is not a bad thing,” Marles told Sky News on Sunday.

He believed the early signs coming out of China, an ally of North Korea, were positive, it saying if the problem is going to be dealt with it needs to be through “China, America and the whole world”.

He said Australia’s global economic interaction was in large measure in that precise part of the world with its major trading partners being China, Japan and South Korea.

“So we have an enormous interest in a stable Korean peninsula and stability in that region,” he said.

North Korea accused the Australian government of “blindly and zealously toeing the US line” and said Ms Bishop had “better think twice” about the consequences of her “reckless tongue-lashing”.

“The Australian foreign minister had better think twice about the consequences to be entailed by her reckless tongue-lashing before flattering the US,” it said.

It said Australia was shielding a hostile US policy of nuclear threats and blackmail against North Korea which was the root cause of the current crisis on the Korean Peninsula and encouraged the US to opt for “reckless and risky military actions”.

“The present government of Australia is blindly and zealously toeing the US line.”

The report said the situation on the Korean Peninsula was “inching close to the brink of war in an evil cycle of increasing tensions”.

PENCE’S HARBOUR CRUISE

The ratcheting up of rhetoric between Australia and North Korea came as Vice-President Pence enjoyed time on Sydney Harbour on Sunday after a day filling with diplomacy on Saturday.

A massive security team, including teams of armed NSW and Federal police plus a contingent of US Secret Service agents and the odd Navy boat, was in place on the water and in the air as Mr Pence, his wife Karen and daughters Charlotte and Audrey joined NSW Premier Gladys Berejiklian for an hour-long trip on board a cruiser, ironically bearing the name Enigma.

Couldn't visit Australia without seeing the kangaroos. Karen, Charlotte, Audrey and I enjoying our morning visit to @tarongazoo. #VPinAUS pic.twitter.com/wMhKnhHxcb — Vice President Pence (@VP) April 23, 2017

As a rivercat carrying US and local media trailed alongside them amongst the police and naval boats, the Pence family took in sights including the Harbour Bridge, Opera House, Fort Denison, Goat Island and Admiralty House, where the vice president held talks with Prime Minister Malcolm Turnbull on Saturday.

As they learned more about Sydney’s famous landmarks, Mr Pence was expected to discuss potential US investment opportunities in NSW.

Ms Berejiklian announced plans on Sunday for Sydney to host a local version of the LAUNCH Festival, the world’s largest startup event which attracts 15,000 people when it’s held in San Francisco each year.

Sydney will host the festival in 2018 and 2019 which Ms Berejiklian says will be a real-life equivalent to the hit TV show Shark Tank.

Earlier in the day, the Pence family spent time meeting some furry friends at Taronga Zoo.

They are due to meet NSW Governor David Hurley and his wife Linda at NSW Government House before taking a private tour of the Opera House.

‘AN ACT AGAINST PEACE’

Earlier this week, Ms Bishop told the ABC that North Korea’s nuclear weapons program posed a “serious threat” to Australia unless it was stopped by the international community.

The KCNA report said that what Ms Bishop had said “can never be pardoned” as it was “an act against peace” and North Korea’s “entirely just steps for self defence”.

US Vice-President Mike Pence is in Australia and the threat of North Korea’s nuclear weapons and missiles programs were high on the agenda in talks with Prime Minister Malcolm Turnbull.

Mr Pence would not rule out the use of military force in North Korea but said “all options are on the table” and he stressed the US was focused on diplomacy at this stage.

He continued the pressure on the rogue state during his visit saying the US supercarrier Carl Vinson will arrive in the Sea of Japan in days, after the mixed messages from Washington over the warship’s whereabouts.

The strike group was supposedly steaming towards North Korea last week amid soaring tensions over the rogue state’s apparent ramping up for a sixth nuclear test, with Pyongyang threatening to hit back at any provocation.

Experts told The Hill that the US is unlikely to have been behind North Korea’s botched missile launch last week, despite rampant speculation that the explosion was the result of an Obama-era cyber sabotage program.

“North Korea is pushing really hard to pursue ballistic missiles. Any accelerated program experiences many failures,” said Joseph Bermudez, an analyst for 38 North, a program of the U.S.-Korea Institute at Johns Hopkins School of Advanced International Studies.

“The probability is higher for this to be failures produced by an aggressive program with limited resources.”

But the US Navy, which had earlier said the aircraft carrier would sail north from waters off Singapore as a “prudent measure” to deter the regime, admitted on Tuesday the ships were in fact sent away from Singapore and towards Australia to conduct drills with the Australian navy.

The aircraft carrier will arrive “in a matter of days”, Mr Pence said.

Also on Saturday North Korea appeared to take aim at China in a thinly veiled warning of catastrophic consequences to their bilateral relations, as it asked its historic ally not to step up sanctions.

The warning came in a commentary titled “Are you good at dancing to the tune of others”, released by the state-owned KCNA news agency. While the commentary did not mention China by name, Pyongyang expressed its criticism of “a country around the DPRK”.

“The country is talking rubbish that the DPRK has to reconsider the importance of relations with it and that it can help preserve security of the DPRK and offer necessary support and aid for its economic prosperity, claiming the latter will not be able to survive the strict ‘economic sanctions’ by someone,” the commentary said.

It added that if “the country” continues applying sanctions on Pyongyang, “it may be applauded by the enemies of the DPRK, but it should get itself ready to face the catastrophic consequences” in bilateral relations.

In February, Beijing announced that it would not buy coal - North Korea’s main export - from Pyongyang for the rest of the year in support of a United Nations resolution.

Official media in China have also suggested the possibility of suspending exports of hydrocarbons if North Korea conducts a new nuclear test. Pyongyang’s apparent criticism of its principal ally, although made indirectly, reflects an estrangement between Beijing and the increasingly isolated regime of Kim Jong Un.