The commander of US forces in South Korea said Friday that North Korea likely has the ability to produce a nuclear warhead that could be mounted on a missile, but officials later sought to downplay his remarks.

The comments by the commander echoed an internal debate among US spy agencies that came to light last year, in which the military's intelligence service warned the North was closer to achieving a nuclear-tipped missile than previously believed.

General Curtis Scaparrotti told a news conference the North Korean regime's pursuit of atomic weapons had progressed to the point where it could probably create a nuclear device to be fitted on the tip of a missile, a major development in the North's nuclear ambitions.

But the general said he had no evidence to back up his view and that there was no sign the North had tested such a device.

"They've had the right connections, and so I believe have the capability to have miniaturized a device at this point, and they have the technology to potentially actually deliver what they say they have," the general said.

"We have not seen it tested. And I don't think as a commander we can afford the luxury of believing perhaps they haven't gotten there," he said.

Pressed by reporters as to whether North Korea could manufacture a nuclear warhead, Scaparrotti offered a more cautious assessment.

"I'm not saying that I know that by any factual basis, but I believe they probably have the background to do this."

North Korea had "proliferation relationships" with other countries, including Iran and Pakistan, that could help it develop such a device, he said.

A Defense Intelligence Agency report leaked last year concluded North Korea probably had the ability to fit a miniaturized nuclear device on a missile.

The report made headlines but US officials at the time said it did not represent a consensus view of all the country's spy agencies.

The director of national intelligence, James Clapper, said last year that "North Korea has not yet demonstrated the full range of capabilities necessary for a nuclear armed missile."

US intelligence agencies have not changed their fundamental assessment of the North's nuclear program, officials told AFP when asked about Scaparrotti's comments.

Officials have said previously that the North has yet to demonstrate it has a functioning long-range intercontinental missile or a nuclear warhead that could be placed on it.

The Pentagon denied the general had expressed a view that was out of sync with intelligence reports and insisted there was no disagreement about the nature of the threat posed by North Korea.

"We have no reason to doubt the general's belief, but as the general also said, he has no facts or evidence to confirm that," spokesman Rear Admiral John Kirby said.

"So we share his concern, we share his general belief that this is a capability they want to acquire and that they very well could have the miniaturization capability."

Flight departs for North Korea despite Ebola tour ban
Beijing (AFP) Oct 24, 2014 - A commercial flight took off from Beijing for North Korea on Friday, despite travel agencies saying they had been told the isolated state would close its borders to foreign tourists over Ebola fears.

The Air China flight departed Beijing Capital International Airport Friday afternoon with 32 passengers on board, according to the airline's duty manager.

"My visa seems not to be affected," said German traveller Arne Hothan as he waited to board, a day after three travel agencies said Pyongyang was closing its border to foreign tourists.

"The chance of people who travel to North Korea... have the virus is probably very very low, so I think that it's not really a good reason to cancel the visa."

The travel agencies -- including two that are based in China -- issued statements Thursday informing clients that the country was closing itself to tourists until further notice because of the threat of the disease.

The epidemic has killed nearly 4,900 people in West Africa, and some countries have banned travellers and flights from Ebola-hit countries.