Three lawmakers were to attend a women’s empowerment conference in the US capital in late March. But Knesset speaker Reuven Rivlin said he canceled the trip because the unrelated visa denial was “an affront to the entire Knesset.”

The State Department won’t let Michael Ben-Ari of the National Union Party enter the United States because he once belonged to the Kach Party of the slain extremist rabbi, Meir Kahane.

Kahane, who was assassinated in New York 20 years ago, preached expelling Arabs from Israel, the West Bank and Gaza Strip. Israel banned Kach from parliament in 1988 on the grounds that it was racist and Washington designates Kach a terror organization.

On that basis, the US State Department rejected Ben-Ari’s visa application two weeks ago.

In an angry letter to the US ambassador to Israel, Rivlin protested the visa denial, saying the man was a legitimately elected member of parliament.

“The United States’ allegation that a member of Knesset is a terrorist in unacceptable and is an affront to the entire Knesset,” Rivlin said in a statement.

Ben-Ari’s assistant Itamar Ben-Gvir — himself a well-known Kach activist — commended Rivlin’s “strong and moral” stance and accused the US of a larger anti-Israeli bent.

“The Americans disgrace not only Knesset member Ben-Ari, but the entire Israeli Knesset,” he said. “It’s all part of Obama’s anti-Israel bias.”

The US Embassy in Tel Aviv had no comment.