Israeli Prime Minister Benjamin Netanyahu and his defence minister Ehud Barak are trying to convince their cabinet to support an attack on Iran, Israeli newspaper Haaretz reported on Wednesday.
Citing an unnamed senior Israeli official, Haaretz said Netanyahu was working to win a majority in favour of a strike against Iran, but there is currently "a small advantage" in the cabinet for those opposed to an attack.
The report said Netanyahu had scored a significant win by convincing his foreign minister Avigdor Lieberman to throw his support behind a strike, intended to destroy nascent Iranian nuclear capabilities.
But other ministers reportedly remain firmly opposed, with many preferring that any action against Iran be carried out by the United States instead.
The Haaretz report came after days of renewed speculation about Israel's plans for an attack on Iran.
On Monday, Barak denied media reports that he and Netanyahu had already decided to launch an attack against Iran over the opposition of military and intelligence chiefs.
Among those still opposed to an attack, Haaretz said, are interior minister Eli Yishai of the ultra-Orthodox Shas party, intelligence minister Dan Meridor, strategic affairs minister and Netanyahu confidant Moshe Yaalon, and finance minister Yuval Steinitz.
Haaretz said a report on Iran's nuclear capacity expected to be published by the International Atomic Energy Agency on Tuesday next week would have a "decisive effect" on any decision to attack Iran.
The newspaper also cited Western experts as saying any attack on Iran during the winter would be almost impossible because of thick cloud cover, raising questions about when any military action might be launched.
Israel has consistently warned all options remain on the table when it comes to Iran's nuclear programme, which the Jewish state and much of the international community believe masks a drive for nuclear weapons.
Iran denies those charges and says its nuclear programme is for civilian energy purposes only.