Israeli former internal security minister Avi Dichter is to be named home front defence minister, media reported on Tuesday, as speculation grows that the Jewish state will launch an attack on Iran.

Dichter, also a former head of the country's internal intelligence agency Shin Bet, will leave his post in the opposition Kadima party to join the government, media reports said.

The government declined to offer official confirmation that Dichter had been selected for the post, which has reportedly been turned down by a slew of other top officials.

Dichter, whose nomination according to Israeli media will be voted on by the parliament on Thursday, will replace Matan Vilnai, a confidant of Defence Minister Ehud Barak, who left the post to become ambassador to China.

He will take on the task of ensuring Israel's home front defence at a time of growing speculation about the possibility of an Israeli attack against Iran's nuclear programme.

Such an attack could spark multi-front retaliation against the Jewish state, including from militant groups in Gaza and Lebanon's Hezbollah.

Observers in the Jewish state have raised questions in recent weeks about Israel's home front preparedness, and earlier this year an Israeli lawmaker told AFP that the country was "completely unprepared" for the consequences of a war, citing a lack of bomb shelters and gas masks.

Asked about his position on an Israeli strike against Iran, Dichter has said that the Jewish state "must have attack capabilities."

Reports suggest that the majority of Israel's defence and intelligence establishment do not favour an attack on Iran's nuclear programme, which much of the international community fears masks a weapons drive -- a claim vehemently denied by Tehran.

There is concern in Washington that a unilateral Israeli strike may not destroy Iran's underground nuclear facilities, could spark Iranian retaliation worldwide and may drag the United States into another war in the Middle East.

The tension in Israel rose another notch on Sunday when the government began testing an SMS system to warn the public of any missile attack.

Israel is widely suspected to have the region's sole, if undeclared, nuclear arsenal.