US President Donald Trump on Thursday signed executive orders limiting the scope of birthright citizenship, despite the country's top court earlier upholding the constitutionally guaranteed right.

The orders aim to end so-called birth tourism, which is when non-US citizens travel to the United States for the purpose of giving birth within its borders. The orders also aim to exclude persons born to a non-American employee of a foreign embassy and those deemed to be "an alien enemy" from automatic citizenship.

Trump's orders are almost certain to be challenged, after the Supreme Court in June struck down his earlier executive order aimed at ending automatic citizenship for those born in the US, even if their parents are not citizens or do not have permanent legal residency.

In Thursday's orders, Trump claimed that birth tourism "undermines the integrity of the Nation's immigration system by enabling foreign nationals to exploit their temporary admission to obtain permanent immigration-related benefits."

The president has insisted that US citizenship is not open to everyone in the world, while trying to block wealthy women from China and other countries from coming to the US to give birth.

The principle of birthright citizenship is enshrined in the US Constitution's 14th Amendment. Ratified in 1868 following the Civil War, the first sentence of the amendment says, "All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the state wherein they reside."