Sept 12 (Reuters) - Iran said on Saturday that Bahrain's move to normalise relations with Israel meant it would be complicit in Israeli policies which threatened regional security, Iranian state TV reported.

Bahrain's agreement, which was announced by U.S. President Donald Trump on Friday, was partly forged because of shared wariness of Iran.

Iran's foreign ministry said that it would hold the governments of Bahrain and its allies responsible for any insecurity caused by Israel in the Gulf region.

Palestinians fear the moves by Bahrain and its fellow Gulf Arab state, the United Arab Emirates, will weaken a longstanding pan-Arab position that calls for Israeli withdrawal from occupied territory and acceptance of Palestinian statehood in return for normal relations with Arab countries.

Bahrain has become the fourth Arab country to reach an agreement with Israel, which exchanged embassies with Egypt and Jordan decades ago.

The UAE agreed to normalise ties with Israel a month ago under a U.S.-brokered deal due to be signed on Tuesday at a ceremony hosted by Trump, who is seeking re-election on Nov. 3.

"Bahrain's shameful move sacrifices the Palestinian cause and decades of struggle ... at the expense of the U.S. election," Iranian TV quoted a foreign ministry statement as saying.

Bahrain is home to the U.S. Navy's regional headquarters. Saudi Arabia sent troops to the small island state in 2011 to help quell a largely Shi'ite Muslim uprising against the Sunni-dominated leadership.

Predominantly Shi'ite Iran and largely Sunni Saudi Arabia are bitter regional rivals. (Editing by Alexander Smith)