US President Donald Trump on Thursday fanned the “birther” debate to target Kamala Harris, the same controversy he had used for years to question former president Barack Obama’s eligibility for the American presidency.

Harris is the first Black woman and Indian-American to run for vice-president.

Since the announcement of her pick as Democratic candidate Joe Biden’s running mate for the November 3 election, some fringe conservatives have questioned Harris’s eligibility, arguing that while she was born in the US, her parents – mother from India and father from Jamaica – were not naturalised citizens of America at the time.

Therefore, they argued, Harris may not be a “natural born citizen” as required by the US constitution to become president or vice-president.

“I heard it today that she (Harris) doesn’t meet the requirements, and by the way, the lawyer who wrote the piece is highly qualified, very talented,” Trump told reporters on Thursday when asked about questions being raised about Harris being an “anchor baby”, a term often used for children born to non-citizens during visits to the US with the aim of helping the rest of the family immigrate to America. Trump was referring to a column in the Newsweek that first floated this argument.

“I have no idea if that’s right,” Trump added. “I would have assumed the Democrats would’ve checked that out before she gets chosen for vice-president.”

“That’s very serious… they’re saying she doesn’t qualify because she wasn’t born in this country?” the US president questioned.

When told that Harris was indeed born in the US and that her parents may not have been legal residents or naturalised citizens at the time, he said. “I don’t know about it. I just heard about it. I will take a look.”

Harris, 55, was born on October 20, 1964, in Oakland, California, which makes her a natural born citizen, eligible to run for the White House or any other officer in the US. Her parents had met as graduate students at University of California, Berkeley.

Harris’ sister speaks out in defence

The Biden-Harris campaign hadn’t immediately responded to Trump’s tacit support for the unproven theory. Maya Harris, the younger sister of Kamala Harris, later tweeted, “There are no gradations of birtherism. You’re either in or you’re out.”

Trump started the “birther” debate in 2011 when he first seriously considered a run for the White House. He questioned Obama’s eligibility for the presidency, wrongly alleging that he was not born in the US. Obama was born in Hawaii, but he felt compelled to release his birth records.

Years later, Trump acknowledged that he was wrong. But in the intervening years, he used the same strategy to attack Ted Cruz, the last of his challengers in the Republican primaries.

Cruz was born in Calgary, Canada, to a father who was from Cuba and a mother who was a natural born American citizen. Cruz lost the primaries and later went on to support Trump for the White House run.