The World Health Organization promised on Saturday that it would publish a full review of its handling of the Ebola crisis once the outbreak was under control, in response to a leaked document that appeared to acknowledge it had failed to do enough.
The WHO said in a statement that it would not comment on an internal document cited in an Associated Press story on Friday, saying it was a first draft that had not been fact-checked and was "part of an on-going analysis of our response".
"We cannot divert our limited resources from the urgent response to do a detailed analysis of the past response. That review will come, but only after this outbreak is over," the organisation said.
The WHO has been widely criticised for its slow response to the epidemic and its early reassurances, despite repeated public warnings from the medical charity Medecins Sans Frontieres, which was leading the fight against the virus on the ground.
Ebola has killed at least 4,546 people in Liberia, Sierra Leone and Guinea, the WHO said on Friday. However, with at least half the cases going unreported and a 70 percent fatality rate, by WHO estimates, the true toll is probably more than 12,000.
There is no sign of a slowdown in the outbreak, which was first confirmed in March but not declared to be an international public health emergency by WHO until Aug 8.
WHO Director General Margaret Chan has defended her handling of the epidemic.
But the internal document cited by AP said experts should have realized that traditional containment methods wouldn't work in a region with porous borders and broken health systems.
"Nearly everyone involved in the outbreak response failed to see some fairly plain writing on the wall," the document said.
It also said WHO bureaucracy was also to blame, with WHO's Africa head, Luis Sambo, appointed by African member countries, not by Chan. Sambo's tenure is ending at the end of this year.
In the earlier stages of the outbreak, messages from Sambo's office were sometimes out of step with the line from Geneva.
The African office declared Ebola to be "pretty much contained" in Senegal and Nigeria on Sept 22, a claim not backed up by Chan's office, which only declared Senegal to be Ebola-free on Friday and has yet to say the same about Nigeria.
The leaked document also said one of Chan's senior officials, Bruce Aylward, had warned her by email that some of the WHO's partners felt it was "compromising rather than aiding" the Ebola response and that "none of the news about WHO's performance is good."
However, it was only five days later, on receiving an internal letter spelling out the WHO's shortcomings, that Chan was "shocked" by "the first news of this sort to reach her", the leaked document said.
"WHO will not do interviews or explain details on this document until it is completed," said the WHO statement on Saturday.
"WHO believes in transparency and accountability and will release this review when it is fact-checked. For now, WHO's focus is to obtain the resources needed to successfully fight this Ebola outbreak.
"A full review and analysis of global responses to this, the largest-ever Ebola outbreak in history, will be completed and made public once the outbreak is under control. We are a public health organization and our focus right now must be to stop this outbreak and save lives."