America's top judicial body has decided to hear case disputing citizenship by birth.

The US Supreme Court has will hear a landmark case that puts to the test a century-old guarantee: automatic citizenship for people born within US borders.

On day one in office this winter, President Donald Trump enacted a directive aiming to terminate the policy, but the action was struck down by the judiciary after lawsuits were brought forward.

The Supreme Court's ultimate ruling will either affirm citizenship rights for the children of migrants who are in the US undocumented or on temporary visas, or it will end the provision entirely.

Next, the justices will schedule a date to hear the case between the administration and claimants, which comprise parents who are immigrants and their young children.

The Legal Foundation

For over a century and a half, the Fourteenth Amendment has established the rule that anyone born in the country is a American citizen, with exceptions for children born to embassy personnel and personnel of occupying armies.

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

The disputed presidential order sought to refuse citizenship to the children of people who are whether in the US without legal status or are in the country on temporary visas.

The United States is one of about three dozen nations – largely in the North and South America – that award instant citizenship to any person born within their borders.