The leaders of Haiti and Dominican Republic agreed Thursday to cooperate in a campaign aimed at eradicating the last vestiges of malaria from the islands of the Caribbean by 2020.

What remains uncertain is how to fund the roughly $250 million effort, which also aims to eliminate lymphatic filariasis, on the two-nation island of Hispaniola. Former President Jimmy Carter, who helped spur the deal, said he is confident a "constant commitment" from the two countries will wipe out the two diseases.

"If the cooperation continues, there's no doubt we will be successful," Carter said after meeting with Dominican President Leonel Fernandez at the National Palace in Santo Domingo. "Since it's been eliminated everywhere else (in the Caribbean), it's obvious it can be eliminated here."

Some 30,000 people in Haiti and several thousand more across the border in the Dominican Republic suffer each year from malaria, an illness that causes high fevers and flulike symptoms that can be deadly if not treated. Ridding this corner of the world of the disease would also eliminate the threat it could spread to nearby islands, including Jamaica and the Bahamas.

Thousands more on Hispaniola are afflicted with lymphatic filariasis, another mosquito-borne illness that can incapacitate and disfigure those infected by swelling limbs to grotesque proportions.

Carter traveled to the island this week in hopes of broadening a $200,000 pilot project established by the nonprofit Carter Center in several border towns that local health officials say helped curb the spread of the two diseases.

The Atlanta-based center's pilot project distributes nets treated with insecticide for residents to hang over their beds, microscopes to help lab technicians diagnose malaria samples and motorbikes so field workers can zip along cramped alleys to test and treat residents.

The project's funding runs out in April, but Carter said he hopes by then both governments and private foundations can pick up the tab.

That price tag may seem daunting, particularly in Haiti, the poorest country in the Western Hemisphere. But Carter said a 2004 malaria outbreak alone cost the Dominican Republic's tourism industry $200 million.

"The cost will be slightly greater than just to control these diseases and have them exist together," he said.

Carter met briefly with Fernandez before addressing a room crowded with reporters. Fernandez made no public remarks, but embraced Carter. The former president also planned to talk with Haitian President Rene Preval in Port-au-Prince.

Carter said the health initiative could herald a new spirit of cooperation between Haiti and the Dominican Republic.

"All too rarely we have seen the full cooperation of the two countries on anything," he said. "So this is a vivid example of what can be done."