President Barack Obama says he is confident the U.S. Supreme Court will uphold his health care reform law in the face of conservative legal challenges.

Speaking at the White House Monday during a news conference with the Canadian and Mexican leaders, Mr. Obama said that the law is constitutional.

He said it would be “unprecedented” and “extraordinary” if a majority of the nine justices voted to overturn a law passed by a democratically elected U.S. Congress.

Mr. Obama said he is confident that the justices recognize they are an “unelected” group and will not throw out a law that Congress approved.

The Supreme Court began reviewing the health care reform law last week. Conservatives challengers say the part of the law requiring people to buy health insurance is unconstitutional.

The court is expected to issue its ruling in June.