Pope Francis has called both major US presidential candidates “against life” and advised Catholic voters to choose the “lesser evil” when casting their ballots in the November election.

The pontiff said not welcoming migrants – seemingly referring to Trump – is a “grave” sin, and compared Kamala Harris’s stance on abortion to an “assassination”.

“Both are against life, be it the one who kicks out migrants, or be it the one who kills babies,″ the Pope said in rare political comments at a Friday news conference as he wrapped up a 12-day tour through southeast Asia.

The Pope did not refer to Harris or Trump by name in his comments.

American Catholics make up 52 million of the 1.4 billion Catholics globally.

Pope Francis was asked to counsel Catholic voters during the in-flight news conference and noted in his remarks that he was not an American and would not be voting in the election.

But he encouraged Americans to vote.

“Not voting is ugly. It is not good. You must vote,” he said.

“You must choose the lesser evil. Who is the lesser evil? That lady, or that gentleman? I don’t know. Everyone, in conscience, (has to) think and do this.”

The Pope has frequently criticised abortion, which is forbidden by Catholic teaching, in sharp terms.

“Forcing a child from the mother’s womb is an assassination because there is life there,” Francis said.

And this is not his first time making critical comments about Trump.

During the 2016 election, he described Trump as “not Christian” because of the presidential contender’s anti-immigrant language.

“Expelling migrants, not letting them develop, not letting them have a life is an ugly thing, it’s mean,” he said on Friday.

Trump has repeatedly promised to crack down on illegal immigration and as recently as Friday afternoon said he would deport millions of immigrants if re-elected.

Harris has promised to expand nationwide protections for access to abortion after the Supreme Court overturned Roe v. Wade in 2022.

Pope Francis’s remarks come days after Trump and Harris debated one another for the first time. The pair was expected to take the debate stage one more time before election day, but Trump has said he would not debate Harris again.