The US Senate unveiled on Wednesday night a health care reform bill that was estimated to cost nearly 850 billion US dollars.

Senate Majority Leader Harry Reid told a press conference that the overhaul health care reform bill would expand health insurance coverage to 30 million more Americans.

Citing an analysis by the Congressional Budget Office, Reid, a Democrat, said that the bill was estimated to cost 849 billion dollars over 10 years but it can reduce the federal deficit by 127 billion dollars in the first decade and more than 600 billion dollars in the following decade.

The 2,074-page bill, which combines two separate drafts approved by Senate committees, will be sent to the whole floor for debate and vote, Reid said.

The long-awaited bill was finally made public after Reid held a close-door meeting with Senate Democrats late afternoon.

He told reporters that public option, one of the most controversial issues about the health care reform, is included in the Senate bill, but states reserve their right to opt out after the bill is put into practice.

The bill would also cease practices including denying coverage to individuals with pre-existing conditions, and raise Medicare payroll taxes for the wealthiest Americans to help pay for the social insurance program for the elderly.

"For too long, health insurance companies have put profits before patients. This is the moment to change that," Senate Finance Committee Chairman Max Baucus said.

The House of Representative approved its health care reform bill on Nov. 7 by a narrow margin of 220 to 215. But, in the Senate, the bill needs 60 out of 100 votes to be passed.

Reid said that he was "cautiously optimistic" he can win the 60 votes, which is the exact number of Democratic and Democratic-lean senators, needed to begin the debate on Friday or Saturday, the first step to have the bill passed.

President Barack Obama has set a deadline for the health care reform bill to be sent to him by the end of the year, but it is likely to be missed due to strong opposition from Republicans and conservative Democrats in Congress.

Right after the release of the Senate bill, Obama issued a statement, applauding the legislation as "another critical milestone" in the push for health care reform.

"I look forward to working with the Senate and House to get a finished bill to my desk as soon as possible," he said.