Britain is sending 750 military personnel, a medical ship and three helicopters to Sierra Leone to help fight the spread of Ebola, officials said Wednesday.

The ship will be equipped with hospital-style critical care units while the three Merlin helicopters will carry doctors to areas where they are needed.

The personnel will be deployed from next week and will help to build treatment centres, the defence ministry said.

It said 200 military personnel would be deployed to run and staff a training facility for medical workers and 250 would use the helicopters to transport supplies and doctors.

The remaining 300 were already planned to assist Sierra Leone's government.

The announcement came after British Prime Minister David Cameron chaired a meeting of the Cobra emergency committee on the spread of Ebola.

The government meeting also decided to step up precautions against Ebola in Britain including through a planned "national exercise and wider resilience training".

The government said in a statement that posters would also be put up in British airports to raise awareness.

In Washington, US Secretary of State John Kerry urged more countries to "step up" in the fight against Ebola following talks with Britain's Foreign Secretary Philip Hammond.

The Ebola epidemic has killed nearly 3,900 people this year, with Liberia, Guinea and Sierra Leone worst hit.

Concerns about the spread of the virus have heightened since a Spanish nurse caught Ebola while treating a patient in a Madrid hospital and the World Health Organization has warned that other isolated infections in Europe were "unavoidable".

Health officials in the US announced Wednesday that a Liberian man diagnosed with Ebola in Texas, Thomas Eric Duncan, had died.

- 'More suspicion needed' -

Britain has only treated one case of Ebola on its shores.

William Pooley, a nurse who contracted the virus while working in Sierra Leone, made a full recovery last month after being treated in a London's Royal Free Hospital.

The Daily Telegraph reported that three additional National Health Service (NHS) hospitals had been identified to take patients, and would be sent equipment if the need arose, in the English cities of Liverpool, Newcastle and Sheffield.

"It is now entirely possible that someone with Ebola will come to the UK by one route or another but we have very, very good plans in place," said Health Secretary Jeremy Hunt.

"The NHS has a proven track record of dealing with and helping people with Ebola. Our ambulance services are equipped with the protective suits."

Britain's trade union for doctors, the British Medical Association, urged ministers to make it easier for doctors from west Africa working in Britain to return to the region and treat Ebola victims.

Many are currently concerned that doing so would put their ability to return to Britain at risk due to visa issues, said BMA senior director Vivienne Nathanson.

She also warned that Britain needed to have a "higher level of suspicion" about the risk from Ebola.

"We know there is a risk associated with the numbers of people coming through London because of our air links to west Africa so we need to have a higher level of suspicion and that means we need to inform the public," she told BBC radio.

"The one thing we have learnt from Texas is that we need to have a higher level of suspicion."