America's top judicial body agrees to review case challenging automatic citizenship for those born in the US.

The US Supreme Court has will hear a significant case that puts to the test a longstanding principle: automatic citizenship for people born on American soil.

On his first day in office this January, President Donald Trump enacted a directive aiming to halt the policy, but the action was subsequently blocked by lower courts after legal challenges were initiated.

The Supreme Court's ultimate ruling will either affirm citizenship rights for the children of immigrants who are in the US without authorization or on short-term permits, or it will overturn them completely.

Next, the justices will schedule a date to hear arguments between the federal government and the suing parties, which include immigrant parents and their newborns.

The 14th Amendment

For nearly 160 years, the Constitutional amendment has enshrined the principle that every person born in the United States is a citizen, with certain exclusions for children born to embassy personnel and members of occupying armies.

"Anyone born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States."

The contested directive sought to refuse citizenship to the offspring of people who are either in the US in violation of immigration law or are in the country on temporary visas.

The United States is one of about three dozen nations – mostly in the Western Hemisphere – that provide immediate citizenship to anyone born in their territory.