The World Health Organization (WHO) says there has been a decline in the spread of Ebola in Liberia, the country hardest hit in the outbreak.

The WHO's Bruce Aylward said it was confident the response to the virus was now gaining the upper hand.

But he warned against any suggestion that the crisis was over.

He said the new number of cases globally was 13,703 and that the death toll, to be published later on Wednesday, would probably pass 5,000.

'Pet tiger'

The figure of 13,703 is a significant leap on the previous WHO situation report on Saturday, which showed cases rising above 10,000 for the first time - to 10,141.

But Dr Aylward, the WHO's assistant director general, said that this increase was due to data being updated with old cases, rather than new cases being reported.

Saturday's situation report put the death toll at 4,922.

Liberia's Red Cross said its teams collected 117 bodies last week, down from a high of 315 in September.

Treatment centres also have empty beds available for patients.

Dr Aylward said : "It appears that the trend is real in Liberia and there may indeed be a slowing."

"Do we feel confident that the response is now getting an upper hand on the virus? Yes, we are seeing a slowing rate of new cases, very definitely."

Dr Aylward said there had been "a huge effort to inform the population about the disease, to change the behaviours that put them at risk".

And he said there had been "a real step up in the work to put in place safe burials".

But Dr Aylward said the data was still being examined and cautioned against thinking the crisis was over.