The United States federal government partially shut down as the clock struck midnight Monday, after Congress failed to pass a budget to fund the federal government into fiscal year 2014.

House Republicans and Senate Democrats were unable to reconcile their differences on the Affordable Healthcare Act, known as 'Obamacare'.

President Barack Obama released this message to U.S. troops, moments after the clock struck midnight.

SOUNDBITE (English) U.S. PRESIDENT BARACK OBAMA SAYING:

"I know the days ahead could mean more uncertainty, including possible furloughs...And I know this comes on top of the furloughs that many of you already endured this summer. You and your families deserve better than the dysfunction we're seeing in Congress."

The consequences of the shutdown mean at least 1 million federal employees could face see cuts in their paychecks.

Military personnel are set to continue on normal duty status but many department of defense civilian employees could be furloughed.

National parks are set to close resulting in 750,000 daily visitors being shut out and an economic loss of $30 million dollars per day.

D.C. tourists attractions including all Smithsonian museums, the National Zoo, the Library of Congress, and perhaps the Lincoln Memorial, are set to possibly close as well.

It is unknown how long the first federal shutdown in 17 years could last.