Britain pledged Wednesday to contribute £20 million to the funding of a campaign spearheaded by former US president Jimmy Carter that aims to eradicate a debilitating parasitic disease by 2015.
Carter is appealing for $70 million (£45.3 million, 52.6 million euros) to eradicate guinea worm, a water-borne infection that causes agonising pain and leaves sufferers unable to function for months.
Britain will contribute to the Carter Center, the former president's humanitarian organisation that is coordinating the campaign, providing other donors come forward to back the scheme.
Carter, 87, has been working to wipe out the disease since 1986 when the Carter Center began an eradication programme.
At a press conference in London, Carter said: "We have a policy at our centre of undertaking difficult projects, quite often which no one else wants to adopt. And perhaps one of the most vivid examples of this has been with guinea worm."
There is no known cure or vaccine to prevent the spread of the disease. The funds will be used to educate people about how to avoid guinea worm and provide an extended surveillance period to guarantee the disease does not return.
"We've had to do a lot of diplomacy and convincing the people there to take care of their own problems," Carter said. "Now almost every nation on earth has eradicated or eliminated guinea worm."
In the mid-1980s, 3.5 million people in 20 countries were infected with the disease. Fewer than 1,800 cases were reported in 2010.
Apart from an isolated outbreak in Chad, guinea worm disease exists only in South Sudan, Ethiopia and Mali.
If the campaign succeeds, guinea worm will become the first parasitic disease to be eradicated and only the second human disease to wiped out worldwide after smallpox in 1979.