Image caption Mr Obama said he would be "extraordinarily proud" of the legacy of the Affordable Care Act

President Barack Obama has defended his healthcare reform law, known as Obamacare, describing it as a legacy to be proud of.

In a TV interview, Mr Obama accepted that problems with the website had affected his popularity, but said every president went through rough times.

Obamacare was intended to extend health insurance coverage to some of the estimated 15% of Americans who lack it.

The government has set a 30 November deadline to overhaul the website.

Mr Obama said his priority now was to make sure the website worked.

As the deadline approached, the controversial HealthCare.gov site was taken down on Friday night for maintenance and upgrades to the software and hardware systems. It was due to go back online on Saturday morning.

In an interview with ABC News, President Obama said he still believed his Affordable Care Act would make good on his manifesto promise to deliver affordable health care to Americans.

The good thing about when you're down is that usually you got nowhere to go but up President Obama

"I continue to believe and [I'm] absolutely convinced that, at the end of the day, people are going to look back at the work we've done to make sure that in this country you don't go bankrupt when you get sick, that families have that security," said President Obama.

"That is going be a legacy I am extraordinarily proud of."

Obamacare has come under constant fire from Republican party critics and many private health providers, who say it is too expensive and an unwarranted intrusion into the affairs of private businesses and individuals.

But opposition intensified after a succession of technical glitches accompanied the launch of HealthCare.gov in October.

Only 27,000 people were able to use the website to sign up in the first month, and there is still a backlog of Americans attempting to meet the deadline of 23 December to be guaranteed cover from 1 January 2014.

Obamacare setbacks Nov 27: Year's delay in online insurance enrolment for small businesses

Year's delay in online insurance enrolment for small businesses Nov 26: Spanish-language sign-up tool is postponed until December

Spanish-language sign-up tool is postponed until December Nov 22: Enrolment deadline for individuals is pushed back a week in December

Enrolment deadline for individuals is pushed back a week in December Nov 14: Obama announces insurers can keep customers on existing plans for another year

Obama announces insurers can keep customers on existing plans for another year Oct 23: Deadline for individuals to avoid penalties is pushed back six weeks to March 2014

Deadline for individuals to avoid penalties is pushed back six weeks to March 2014 July: Businesses with over 50 workers given until 2015 to provide insurance or pay a penalty

According to an ABC News-Washington Post poll released last week, the president's job approval rating fell to 42%, down 13 percentage points this year and 6 points in the past month.

But Mr Obama said he was used to difficult periods in his presidency.

"The good thing about when you're down is that usually you got nowhere to go but up," he said.

The problems with the website have forced Mr Obama to apologise for "fumbling the ball" by not delivering a more successful launch, while Republicans have accused the president of breaking his promises.

Seated alongside his wife Michelle, Mr Obama referred to criticism that he had appeared not to be aware of the extent of problems with the website, which his administration has promised to deal with by the end of November.

"We're evaluating why it is exactly that I didn't know soon enough that [it] wasn't going to work the way it needed to," Mr Obama said. "But my priority now has been to just make sure that it works."

In the interview with ABC News's Barbara Walters, being aired in the United States at 22:00 EST, Mr Obama also suggested that his family may stay in Washington after the end of his second term, due in part to considerations of the continuing education of his daughter Sasha.