US President Donald Trump plans to push an executive order to end the right of US citizenship to children born in the United States to non-citizens and immigrants who are in the country illegally.

It was unclear what specific action his order would pursue, and Mr Trump gave no other details.

Mr Trump has stepped up his hard-line immigration stance one week before US congressional elections, as the country grapples with race and national identity amid bursts of violence, including a series of bombs sent to top Democrats and other Trump critics as well as the deadliest attack on a synagogue in US history.

Seeking to end so-called birthright citizenship outlined in the 14th Amendment would take direct aim at the US constitution and likely prompt immediately legal challenges and potential opposition in Congress.

Changing an amendment in the US constitution would require the support of two-thirds of the US House of Representatives and the Senate and the backing of three-fourths of US state legislatures at a constitutional convention.

But in an interview to Axios, Mr Trump said he has talked to his legal counsel and was advised he could enact the change on his own, contrary to the view of many constitutional experts.

Asked about the dispute over such presidential powers, Mr Trump said: "You can definitely do it with an act of Congress. But now they're saying I can do it just with an executive order."

"It's in the process. It'll happen," he told Axios in the interview, which will air in full on HBO on Sunday.

One member of Congress, Republican US Senator Lindsey Graham, said he would move forward to introduce legislation "along the same lines" as Mr Trump's order.

Neither Mr Graham nor Mr Trump gave any details about the plan, and the White House did not respond to a request for comment.

However, the Republican leader in Congress has said it is not possible to end birthright citizenship with an executive order.

"You cannot end birthright citizenship with an executive order," the Washington Post has quoted Paul Ryan as saying.

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US Senator Chris Coons, a Democrat on the Senate Foreign Relations Committee, said that Mr Trump "was driving a false narrative on immigration" in many ways to stoke fear ahead of the 6 November vote.

The 14th Amendment allows for "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."

A legal challenge would prompt the nation's courts to weigh in on what would be one of the most sweeping moves of the Trump administration.

It has already targeted immigration through a travel ban from several Muslim-majority countries, child-parent separations for migrants, refugee policies and other actions.

In 1898, the US Supreme Court reaffirmed the right of citizenship to children born to legal permanent residents.

But conservatives say that right should not apply to everyone, including immigrants in the country illegally or those with temporary legal status, Axios reported.

Vice President Mike Pence said the plan may not be unconstitutional, telling Politico in an interview that while "we all cherish" the 14th amendment, the nation's top court has not weighed in on the issue entirely.

Mr Trump, who railed against illegal immigration during the 2016 US presidential election, has seized on the issue in recent weeks as he seeks to bolster fellow Republicans ahead of next week's midterms.

Yesterday, his administration moved to send more than 5,200 troops to help secure the border with Mexico as a caravan of Central American migrants makes its way there.

The caravan, moving mostly on foot, is not expected to arrive for several weeks and it was unclear how many would arrive at the border.

Democrats and other critics have decried the president's rhetoric as inflammatory, urging Mr Trump to tone down his language and calling on the electorate to use next week's vote as a way to reject such policies.