The nation's highest court has decided to hear case questioning automatic citizenship for those born in the US.

The top court has will hear a significant case that puts to the test a historic guarantee: birthright citizenship for people born within US borders.

On day one in office this January, President Donald Trump issued an executive order aiming to halt birthright citizenship, but the move was halted by lower courts after lawsuits were brought forward.

The Supreme Court's eventual decision will either support citizenship rights for the children of foreign nationals who are in the US without authorization or on non-immigrant visas, or it will end the provision completely.

Next, the justices will set a time to hear oral arguments between the government and plaintiffs, which include parents who are immigrants and their young children.

A Constitutional Cornerstone

For more than 150 years, the Constitutional amendment has established the principle that all individuals born in the country is a citizen, with specific conditions for children born to diplomats and members of invading forces.

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

The challenged directive sought to withhold citizenship to the offspring of people who are either in the US in violation of immigration law or are in the country on non-permanent visas.

The United States is among about three dozen nations – largely in the Americas – that provide automatic citizenship to anyone born within their borders.