Washington  - The US House of Representatives could vote Saturday evening on a landmark health reform bill that is aimed at cutting costs and extending coverage to Americans who lack insurance.

The House vote would mark the biggest victory yet for President Barack Obama's top domestic priority and comes after months of political wrangling. The road is even tougher in the Senate, which has yet to start debating its own version of the bill.

Leading Democrats in the House were busy Friday working to ensure they had enough votes to pass the measure, which is uniformly opposed by Republicans and has sparked some rebellions within the left- leaning Democratic Party.

Last-minute sticking points that have emerged include how to ensure the bill's provisions do not go towards funding abortions or providing support for illegal immigrants to buy health insurance.

Obama was expected to visit Capitol Hill early Saturday to help prod members of his own party to support the legislation, which includes a controversial government-run insurance option.

The Democrats' House Majority Leader Steny Hoyer predicted the bill would come to a vote Saturday night, but acknowledged the deadline could still be pushed back to Sunday or early next week.

The health care overhaul has been the subject of an extremely divisive political debate for the past year. Democrats, who control both houses of Congress, are pushing for reforms aimed at bending the cost curve of the world's most expensive health care system, which makes up about 16 per cent of the economy.

The bill is projected to cost 894 billion dollars over 10 years, but claims to reduce the federal budget deficit by 104 billion dollars. It will be paid for through efficiency measures and new taxes on the most expensive insurance plans, according to the non- partisan Congressional Budget Office (CBO).

The bill would also force Americans to buy health insurance and increase government subsidies for the poor. The CBO has said the reforms will increase coverage to about 96 per cent of the population, up from 83 per cent.

"We are closer to passing this reform than ever before," Obama said Thursday. He touted two major endorsements from the American Medical Association (AMA), an advocacy group for doctors, and AARP, which represents seniors.

Republicans remain strongly opposed, arguing that the proposals amount to a government takeover of the largely private system. The House vote is expected to be strictly along party lines.

The bill includes a government-run insurance option, which is favoured by left-leaning Democrats but has been a lightning rod for criticism of health reform by conservatives and some moderate Democrats.

Politicians have failed for decades to agree on a comprehensive overhaul of the health care system. The last major reform was approved in the 1960s, when Congress created two government-run insurance options: Medicare for seniors and Medicaid for the poor. (dpa)