|CIA image showing alleged covert nuclear reactor under construction, near Al Kibar, in the eastern desert of Syria
George Bush contemplated ordering a US military strike against a suspected Syrian nuclear facility at Israel's request in 2007, the former US president has reminisced in his memor to be published soon.
Israel eventually destroyed the facility, which Syria denied was for developing a nuclear weapons.
In his memoir, "Decision Points", to hit bookstores on Tuesday, Bush says that he received an intelligence report about a "suspicious, well-hidden facility in the eastern desert of Syria" that looked similar to a nuclear facility at Yongbyon, North Korea.
Shortly afterward, he spoke by phone with Ehud Olmert, then the Israeli prime minister.
"George, I'm asking you to bomb the compound," Olmert told Bush, according to the book, a copy of which was obtained by the Reuters news agency.
Bush said he discussed options with his national security team. A bombing mission was considered "but bombing a sovereign country with no warning or announced justification would create severe blowback," he writes.
A covert raid was discussed, but it was considered too risky to slip a team in and out of Syria undetected.
Bush received an intelligence assessment from then-CIA Director Mike Hayden, who reported that analysts had high confidence the plant housed a nuclear reactor but low confidence of a Syrian nuclear weapons programme.
Bush said he told Olmert, "I cannot justify an attack on a sovereign nation unless my intelligence agencies stand up and say it's a weapons programme."
Bush had ordered the US-led invasion of Iraq in 2003 based on intelligence that said Iraq possessed weapons of mass destruction, which were never found.
Olmert was disappointed by Bush's decision to recommend a strategy of using diplomacy backed up by the threat of force to deal with Syria over the facility.
"Your strategy is very disturbing to me," Olmert told Bush, according to the book.
Bush denies charges that arose at the time that he had given a "green light" for Israel to attack the installation.
"Prime Minister Olmert hadn't asked for a green light and I hadn't given one. He had done what he believed was necessary to protect Israel," Bush says in the book.
In Jerusalem, Olmert's office declined comment on the disclosures in the Bush memoir.
Israel has never formally confirmed carrying out the sortie or targeting a nuclear facility.
The Olmert government was pursuing indirect peace talks with Syria at the time.
But Olmert, who resigned in a corruption scandal in 2008, has recently lifted the veil, speaking of a "daring operation" that he ordered despite opposition.
Bush writes that Olmert's "execution of the strike" against the Syrian compound made up for the confidence he had lost in the Israelis during their 2006 war against Hezbollah in Lebanon, which Bush feels had a mixed outcome.
Lebanon's young democracy emerged from the conflict stronger for having endured the test, Bush says, but "the result for Israel was mixed."
"Its military campaign weakened Hezbollah and helped secure its border. At the same time, the Israelis' shaky military performance cost them international credibility," Bush says.