David Cameron has called for EU leaders to double their funding in the fight against Ebola to £800 million.
It comes after one of the doctors who discovered the virus, Professor Peter Piot, said the rest of Europe was not doing enough to tackle the epidemic.
Downing Street said the current total contribution from the EU was just £400 million.
More than 20,000 people could be infected by the current outbreak of the Ebola virus, the World Health Organisation said.
They said the actual number of cases in four West African nations could already be two to four times higher than the reported 3,069, as they issued a strategic plan to combat the outbreak.
They said: "The actual number of cases may be 2-4 fold higher than that currently reported."
They added that their road map "acknowledges that the aggregate case load of Ebola Virus Disease could exceed 20,000 over the course of this emergency."
They said: "Response activities must be adapted in areas of very intense transmission and particular attention must be given to stopping transmission in capital cities and major ports, thereby facilitating the larger response and relief effort."
As it reaches seven months since the Ebola outbreak started we take a look at the timeline of events leading up to the spread of the virus.
More than 100 British personnel are arriving in Sierra Leone to combat the Ebola outbreak in West Africa. Here's what else the UK is doing.
A man has been filmed helping an Ebola patient onto a plane without wearing any protective equipment.