Even Washington's all-powerful Israel lobby has criticised Netanyahu for pact with racists

An influential American pro-Israel lobby group has made a rare criticism of Israel's government over a controversial electoral pact struck between Prime Minister Binyamin Netanyahu and an extreme ultra-nationalist Jewish party.

The American Israel Public Affairs Committee (AIPAC) described the Jewish Power Party, which entered into the pact with Netanyahu last week, as "racist and reprehensible".

The group also retweeted a statement from the American Jewish Committee, a fellow lobbying group, which criticised the Jewish Power Party.

"The views of Otzma Yehudit are reprehensible," the tweet said, using Jewish Power's Hebrew name. "They do not reflect the core values that are the very foundation of the State of Israel."

Jewish Power is a hugely controversial group which embraces the ideas of the late rabbi Meir Kahane, who want to establish a Jewish theocracy and have advocated the forced removal of Palestinian citizens from Israel.

Kahanists have carried out deadly attacks against Palestinians, including in 2005 when a 19-year-old Israeli soldier affiliated with the Kach Party deserted his unit and opened fire on a bus, killing four Palestinian-Israelis. 

A Kach supporter, Baruch Goldstein, was also behind the Ibrahimi Mosque massacre in 1994, when 29 people were shot to death at the prominent Hebron religious site.

The Kach movement has been classified as a terrorist organisation by Washington since 1997.

Jewish Power responded to AIPAC's criticism Netanyahu's electoral pact by saying that the group's members should "come home before interfering in the election".

Netanyahu, meanwhile, has remained silent in the face of Jewish-American criticism of the controversial deal, while blasting his critics at home.

The Israeli leader is due to speak at AIPAC's policy conference next month.