NEW YORK (REUTERS) - President Barack Obama teamed up with his one-time rivals Bill and Hillary Clinton on Tuesday to highlight the benefits of US healthcare reform, a week before one of the controversial law's key elements, new insurance exchanges, go live.

Mr Obama, who was in New York for the UN General Assembly, joined the former president for a talk-show-like session at the Clinton Global Initiative (CGI) conference and urged Americans to become informed about measures designed to ensure millions of uninsured Americans get coverage.

The White House has battled Republican efforts to discredit the law, known as Obamacare. The House of Representatives passed a bill last week that would fund the US government beginning Oct. 1 only if the law is ransacked.

Seeking to allay fears and reduce confusion, Mr Obama urged Americans to tune out naysayers and inform themselves directly by reading the website healthcare.gov before signing up for affordable care.

"The main message we have ... is look, just go to the website yourself," Mr Obama said. "When people look and see that they can get high-quality, affordable healthcare for less than their cellphone bill, they're going to sign up."

His presence at CGI was steeped in politics, both past and present. He beat Mrs Hillary Clinton for their party's 2008 presidential nomination, and tension with her husband lingered even after Mr Obama made her secretary of state in his first term.

The former first lady is now the unofficial frontrunner for the Democratic nomination in 2016 if she decides to run again, and the Clintons are likely to seek Mr Obama's backing if she does.

Mr Clinton campaigned extensively for Mr Obama in 2012 and the two men largely overcame their differences. Mr Clinton gave a speech earlier this month as part of the White House's healthcare law rollout.

Mr Clinton tried to overhaul the healthcare system in the early 1990s when he was president, but that effort - spearheaded by his wife - failed in Congress. Their attempt called attention to millions of Americans who lacked health insurance.

Mr Obama nodded to their work after Mrs Clinton introduced him and her husband before the two men came on stage.

"The person who just introduced us, as well as you early in your presidency, had as much to do with helping to shape the conversation as anybody," Mr Obama said to the former president.

Mrs Clinton, who has made the family foundation her base while she mulls another presidential run, joked about the former and current occupants of the Oval Office.

"I thought hard about how to introduce these two men. And the more I thought about it, the more I realised how much they have in common," she said, listing their left-handedness and implying they both have shaky golf skills.

"They are both Democrats. They have fabulous daughters. They each married far above themselves," she said to laugher.

Once Mr Clinton and Mr Obama entered the stage, they got off to a somewhat awkward start before getting into a conversation with sometimes wordy explanations about the benefits of healthcare reform.

Mr Obama, who made a point of saying he missed having Mrs Clinton in his administration, accused his opponents of peddling misinformation about the law, particularly in the last month.

"Those who have opposed the idea of universal healthcare in the first place and have fought this thing tooth and nail through Congress and through the courts and so forth have been trying to scare and discourage people from getting a good deal," he said.

The event took place one week before the new healthcare exchanges open. The exchanges will allow millions of Americans who do not have insurance to sign up for plans that fit their budgets, the White House says.

The event also comes one day after the 20th anniversary of Mr Clinton's call for healthcare reform in a speech to Congress.