Sanders, who is Jewish, urged Mamdani to be cautious about how he approaches talking about Israel. Both are critics of Israeli Prime Minister Benjamin Netanyahu and Israel’s handling of its war in Gaza.

Ahead of the trip, Mamdani told business leaders in New York that he would discourage the use of the phrase “globalize the intifada.” Mamdani, who has not used the phrase himself, has said he believes the phrase to be a rallying cry for Palestinian human rights and refused to condemn its use when asked during his primary campaign.

According to the person familiar with their conversation, Sanders told Mamdani he had to do a better job explaining that his criticism is not antisemitic and to not let himself seem like he’s minimizing the fear Jews in New York and elsewhere feel from the threat of hate against them.