Tue Jan 6, 2009 4:40pm EST

CARACAS, Jan 6 (Reuters) - Venezuela expelled the ambassador to Israel on Tuesday in protest over the offensive in Gaza only hours after leftist President Hugo Chavez called the attacks a Palestinian "holocaust."

The socialist Chavez, a harsh critic of Israel and the United States, in recent years has frequently withdrawn Venezuela's diplomatic envoys amid bilateral disputes and last year kicked out the U.S. ambassador over a conflict involving allied Bolivia.

The OPEC nation's Foreign Ministry said in a statement that Israel's campaign constituted "flagrant violations of International Law" and the use of "state terrorism."

"For the reasons mentioned above, the government of Venezuela has decided to expel the Ambassador of Israel and part of the personnel of the Embassy of Israel," the statement said.

The Israeli embassy did not respond to phone calls requesting comment.

Chavez in 2006 threatened to break ties with Israel over its military campaign in Lebanon in a war of words that led both nations to withdraw their envoys.

On Monday he accused Washington of poisoning the late Palestinian leader Yasser Arafat to destabilize the Middle East and justify U.S.-backed Israeli incursions into Arab countries.

Israel is under international pressure to reach a ceasefire with Hamas militants and halt an offensive that has killed nearly 600 Palestinians, including more than 40 in a U.N. school sheltering civilians.

"The Holocaust, that is what is happening right now in Gaza," Chavez said in televised comments earlier on Tuesday.

"The president of Israel at this moment should be taken to the International Criminal Court together with the President of the United States."

The United States, which Chavez describes as a decadent empire, firmly backs Israel -- its principal ally in the region.

(Reporting by Brian Ellsworth; Editing by Sandra Maler)