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.
The president of Sierra Leone has declared a public health emergency in an attempt to fight the worst ever outbreak of Ebola.
Security forces will be used to quarantine epicentres of the deadly virus, President Ernest Bai Koroma said.
He has also cancelled a trip to Washington for a US-Africa summit next week due to the crisis.
The tough measures being brought in are similar to those announced by Liberia on Wednesday.
Some 672 people have died from Ebola across Liberia, Guinea and Sierra Leone, according to the World Health Organisation.
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.