'The time for bickering is over. The time for games has passed. Now is the season for action,' he said.

Obama, who has so far left the crafting of the legislation largely to Congress, delivered a series of more concrete proposals during the rare address before a joint session of Congress.

He broke a presidential campaign pledge not to require insurance coverage, arguing that the system can no longer allow younger or middle-income families to 'game the system'. Everyone would have to 'carry basic health insurance'.

Obama stood by the creation of a public insurance option that has been sharply opposed by conservatives. He insisted that such an option would not receive taxpayer subsidies and was necessary as a counterbalance to private insurance companies.

But Obama suggested the public option was simply a 'means to an end' and said that Democrats should 'remain open to other ideas that accomplish our ultimate goal'.

He insisted that about 80 percent of the reform plans could already be agreed on. That includes barring insurance companies from dropping consumers with pre-existing health conditions and creating a national 'health exchange' that would allow consumers to shop for insurance plans across state lines.

Obama said he remained open to proposals from both parties, but cautioned: 'I will not waste time with those who have made the calculation that it's better politics to kill this plan than improve it.'

Obama has an uphill battle in overhauling health care coverage in the US, which has the costliest system in the industrialised world and leaves about 46 million people uninsured. There have been no major reforms approved in four decades.