Turkish President Recep Tayyip Erdogan on Tuesday branded Israel the "most fascist, racist state" in the world after Israel's parliament passed a new law defining the country as the nation-state of the Jewish people.
"This measure has shown without leaving the slightest room for doubt that Israel is the world's most Zionist, fascist and racist state," Erdogan said in a speech to his ruling party.
In one of his toughest recent onslaughts against Israel, Erdogan claimed there was "no difference between Hitler's obsession with the Aryan race and Israel's understanding that these ancient lands are meant only for Jews."
"The spirit of Hitler, which led the world to a great catastrophe, has found its resurgence among some of Israel's leaders," he added.
Around six million Jews were killed in the Holocaust by the Nazis during World War II.
The legislation, adopted after a tumultuous Knesset session, makes Hebrew the national language and defines the establishment of Jewish communities as being in the national interest.
Arabic, previously considered an official language, was granted only special status.
For his part, Israel's prime minister angrily rebuffed comments by the Turkish president, accusing him of "massacring Syrian and Kurds."
Netanyahu tweeted that under Erdogan's rule, Turkey had become a "dark dictatorship".
The two countries have a recent history of tense relations.
Once close allies, Turkey broke off diplomatic ties with Israel in 2010 after 10 pro-Palestinian Turkish activists were killed in clashes with Israeli commandos who boarded a Turkish-owned ship trying to break Israel's maritime blockade of the Gaza Strip.
Relations were restored in 2016, but they expelled each other's top diplomats in May this year in a dispute over Israel's killing of Palestinians amid protests on the Gaza border.
Human rights groups have accused Israeli troops of using excessive force. Israel says they only opened fire in self-defense or on Palestinians trying to infiltrate its territory under the cover of the demonstrations to carry out attacks.