SEOUL (Reuters) - North Korea will bar entry to foreigners on tourist trips from Friday, because of worries over the spread of the deadly Ebola virus, operators of tours to the isolated country said.

It was not immediately clear if the North Korean ban also covered non-tourist members of the diplomatic or business community with ties to Pyongyang.

"We have just received official news from our partners in the DPRK that, as of tomorrow, tourists from any country, regardless of where they have recently visited, will not be permitted to enter," said Gareth Johnson of Young Pioneer Tours, a travel company based in China that runs tours in North Korea.

DPRK is short for the North's official name, the Democratic People's Republic of Korea.

At least 4,877 people have died in the world's worst recorded outbreak of Ebola, the World Health Organization (WHO) estimates, with nearly 10,000 cases recorded by Oct 19, though the true toll could be three times as much.

In late September, the North's official news agency, KCNA, said it was stepping up quarantine efforts to detect foreigners and tourists who might be carrying the virus.

Other travel agents specialising in tours to North Korea confirmed the news, which they said came through official channels in Pyongyang and Beijing. "It is unknown how long this closure will be in effect, and due to the very changeable nature of DPRK policy, we are still hopeful we will be able to run the three tours we have scheduled for the remainder of 2014," said Nick Bonner of Koryo Tours, a travel group based in Beijing that also specialises in North Korea tours.

International travel to North Korea is rare and although there have been no reported cases of the Ebola virus in the reclusive country, in the past it has sealed its borders to foreign visitors over health concerns.

"In 2003, the country closed its borders due to the threat of SARS, despite not a single case being reported there," said Bonner of Koryo Tours.