US President Barack Obama has made a last-minute appeal to Democrats to give his $1.2 trillion (£723bn) healthcare programme the green light.

The landmark legislation - central to his election campaign last year - aims to expand coverage to millions of uninsured Americans.

President Obama urged his party members in the House of Representatives to push the bill through, whereupon it will head for a vote in the Senate.

"What's in our grasp right now is a chance to prevent a future where every day, 14,000 Americans continue to lose their health insurance, and every year, 18,000Americans die because they don't have it," he said during a statement delivered from the White House Rose Garden.

Earlier, house speaker Nancy Pelosi predicted the bill would be approved following a closed-door meeting with the president.

Not long after Mr Obama left Washington, the legislation cleared its first big hurdle on the House floor.

The lawmakers voted 242-192 to approve a crucial procedural measure setting the terms for the debate.

A total of 15 Democrats dissented, joining all 177 Republicans in voting to block the debate.

Republicans in the House have been united in their opposition to the bill which would impact one-sixth of the US economy.

"The American people need to understand this is about a government takeover of the whole health care system," one Republican said.

The bill would expand health coverage to tens of millions of Americans and require most employers to offer it to their workers.

The proposals would also prohibit insurance companies from denying coverage based on a person's medical history.

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