In a talk laying out the foreign policy principles he would hew to as president, former Vice President Joe Biden said the United States’ relationship with Israel must be “ironclad,” whatever one’s feelings about Prime Minister Binyamin Netanyahu, JTA reports.

Speaking at the City University of New York, Biden stressed the importance of “sustaining our ironclad commitments to Israel’s security regardless of how much you may disagree with its current leader.”

While in office, Biden repeatedly insisted that he was a friend of Netanyahu’s, even amid ongoing tensions between the US and Israel during former President Barack Obama’s term.

At a Rabbinical Assembly convention during the 2012 presidential campaign, Biden told an anecdote about once signing a photo for Netanyahu with this inscription: “I don't agree with a damn thing you say, but I love ya.”

In his remarks on Thursday Biden, who is leading in the polls among 25 Democrats running for their party’s nomination, also said he would re-enter the Iran nuclear deal, from which President Donald Trump withdrew last year.

“If Tehran returns to compliance with the deal I’d rejoin the agreement and work with our allies to strengthen and extend it,” Biden said, “while more effectively pushing back against Iran’s more destabilizing activities which under the agreement we were allowed to do — we had partners to do with us.”

The former Vice President recently criticized President Donald Trump's strategy on Iran as a "self-inflicted disaster" that could push the United States towards war with a major adversary.

As a result of Trump’s move, Biden said, "Iran is building back up its nuclear capability."

While Trump promised that exiting the deal and slapping sanctions on Iran would halt its belligerence in the region, "they've only gotten more aggressive," Biden charged.

While Biden urged the American public to give Trump a chance after he was elected, the two have also locked horns.

During the election campaign, Biden had harsh criticism for Trump, saying he had “no clue”. In another instance, Biden said that Trump “would’ve loved Stalin”.