Former Texas representative and 2020 Democratic presidential candidate Beto O’Roruke slammed Israeli Prime Minister Benjamin Netanyahu on Sunday as a “racist” in response to the latter saying on Saturday that he would annex parts of Judea and Samaria if he wins re-election on Tuesday.

“That relationship, if it is to be successful, must transcend partisanship in the United States, and it must be able to transcend a prime minister who is racist, as he warns about Arabs coming to the polls, who wants to defy any prospect for peace as he threatens to annex the West Bank, and who has sided with a far-right, racist party in order to maintain his hold on power,” said O’Rourke, campaigning in Iowa.

He added that Netanyahu does not exemplify the “true will of the Israeli people” or the “best interests” in the alliance between America and Israel.

The O’Rourke campaign did not immediately respond to a request for comment regarding the candidate’s stance on Palestinian Authority leader Mahmoud Abbas.

Former U.S. Sen. Joe Lieberman disagreed with O’Rourke’s assessment.

“This is an ally in the midst of an election,” he told Fox Business on Monday. “What I would say, and I know Prime Minister Netanyahu a long time, I agree with him a lot of the time, I sometimes disagree—he’s not a racist.”

“I think I understand what Mr. O’Rourke was talking about, which is that one of the groups that is a likely coalition within the Israeli political community, with the prime minister in this election, has some people in it that I don’t agree that have taken … a very … anti-Arab position,” he added.

However, Lieberman said O’Rourke’s remarks were “not fair.”