The nation's highest court has decided to hear lawsuit challenging citizenship by birth.

The US Supreme Court has decided to review a pivotal case that questions a century-old constitutional right: automatic citizenship for people born in the United States.

On his first day in office this January, President Donald Trump enacted a directive aiming to end this practice, but the move was subsequently blocked by lower courts after lawsuits were initiated.

The Supreme Court's eventual decision will ultimately uphold citizenship rights for the children of immigrants who are in the US without authorization or on short-term permits, or it will nullify those rights completely.

Next, the judges will set a time to hear oral arguments between the government and the suing parties, which comprise parents who are immigrants and their infants.

The 14th Amendment

For over a century and a half, the Constitutional amendment has established the principle that anyone born in the United States is a US citizen, with certain exclusions for children born to embassy personnel and personnel 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 executive order sought to deny citizenship to the offspring of people who are whether in the US in violation of immigration law or are in the country on temporary visas.

The United States is among about 30 countries – mostly in the Americas – that award immediate citizenship to anyone born on their soil.