The nation's highest court will review legal challenge disputing birthright citizenship.

The top court has decided to review a pivotal case that puts to the test a century-old guarantee: automatic citizenship for people born within US borders.

On the inaugural day in office this January, President Donald Trump enacted a directive aiming to terminate the policy, but the action was halted by federal courts after constitutional questions were initiated.

The Supreme Court's final judgment will ultimately affirm citizenship rights for the infants of immigrants who are in the US illegally or on non-immigrant visas, or it will overturn them entirely.

Next, the court will calendar a session to hear oral arguments between the government and plaintiffs, which involve parents who are immigrants and their newborns.

A Constitutional Cornerstone

For nearly 160 years, the 14th Amendment has codified the rule that all individuals born in the nation is a American citizen, with exceptions for children born to diplomats 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 challenged presidential order sought to withhold citizenship to the children 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 among about a minority of states – largely in the Western Hemisphere – that award immediate citizenship to anyone born in their territory.