BEIJING (AFP) - Nigeria has withdrawn from the Youth Olympics in the Chinese city of Nanjing, state media reported on Saturday, as four African nations battle the worst outbreak of the Ebola virus in decades.

Nigeria's decision was confirmed by International Olympic Committee (IOC) President Thomas Bach in Nanjing, China's official Xinhua news agency said.

"We feel sad for the athletes as it will be extremely difficult for them," Bach said of the Nigerians, Xinhua reported.

"They already felt the excitement of living in the Village and now they have to leave - that's a very difficult task."

The IOC had said on Friday athletes from Ebola-hit countries would be barred from competing in pool events and combat sports.

The decision, which affects three athletes whose names and nationalities were not identified, was made "to ensure the safety of all those participating", the IOC and the Chinese organisers said.

According to the Youth Olympics' website, there were a total of 25 people on the team lists of Sierra Leone, Liberia, Guinea and Nigeria, the west African countries affected by the outbreak.

The Youth Olympic Games begin on Saturday in Nanjing, China's former capital, and run until Aug 28.

They will feature more than 3,700 competitors aged 14 to 18, some of whom hope to build towards a place in the 2016 Olympic Games in Brazil.

The World Health Organisation said on Friday the death toll from the worst epidemic of the disease in four decades has climbed to 1,145 in the afflicted countries.