The nation's highest court will consider legal challenge questioning citizenship by birth.

The US Supreme Court has will hear a pivotal case that questions a century-old constitutional right: guaranteed citizenship for individuals born on American soil.

On day one in office this winter, President Donald Trump enacted a directive aiming to terminate birthright citizenship, but the order was struck down by lower courts after legal challenges were brought forward.

The Supreme Court's eventual decision will ultimately uphold citizenship rights for the offspring of immigrants who are in the US illegally or on non-immigrant visas, or it will overturn those rights altogether.

Next, the justices will set a time to hear arguments between the administration and the suing parties, which involve foreign-born parents and their newborns.

The 14th Amendment

For over a century and a half, the Constitutional amendment has enshrined the rule that all individuals born in the United States is a citizen, with certain exclusions 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 disputed executive order 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 non-permanent visas.

The United States is among about three dozen nations – primarily in the North and South America – that provide instant citizenship to anyone born in their territory.