The Monday meeting is likely to be their last face-to-face exchange before Bush, who had once hoped to seal an Israeli-Palestinian deal in 2008, hands president-elect Barack Obama the keys to the White House on January 20.

With Bush leaving office and Olmert heading a caretaker government ahead of February elections, the two leaders were unlikely to take any major decisions on any of the outstanding issues.

"The prime minister wants to use the meeting as an opportunity to express his appreciation for President Bush's friendship and support for Israel," Olmert spokesman Mark Regev said.

The two will discuss "a range of bilateral issues, the peace process as well as issues of regional stability," he said, referring to Iran. "We are hopeful for substantive meetings."

A senior US official, who requested anonymity, described the meeting as chiefly a stock-taking effort from which no major announcement should be expected.

Olmert will meet Monday with US Vice President Dick Cheney and was expected to see other top US officials and perhaps aides to the US president-elect.

Olmert wants to clinch new commitments on Iran from his staunch ally before Obama, whose policy towards the Islamic republic has raised some concern in Israel, enters the White House, officials said.

"For Olmert, this is a farewell visit from a close friend and ally. He wants to tie loose ends with regards to promises the Bush administration has given Israel," a government official said.

Olmert will press Bush and Congress to allow Israel to purchase dozens of F-35 stealth fighter jets, which would considerably boost the Israeli air force's ability to carry out long-range strikes.

In September, the Pentagon announced that Israel had asked to buy up to 75 jets, but Congress has yet to give the 15-billion-dollar (12-billion-euro) deal a green light.

Over the past year, the United States has considerably increased its already tight defence ties with its ally, giving the Jewish state an unprecedented 10-year, 30 billion dollar defence aid commitment.

The US military also deployed a powerful missile defence radar in Israel to enhance regional defences against ballistic missiles. Congress was further notified of plans to sell 1,000 bunker-buster bombs to Israel.

The aid comes amid growing US and international concern about Iran's missile and nuclear programmes and statements by Iran's leaders predicting that Israel is doomed to disappear.

Israel, the region's sole if undeclared nuclear armed state, considers Iran its main strategic threat because of its nuclear programme, which Israel and its US ally suspect is aimed at developing an atomic bomb.

Olmert has repeatedly said Israel would prefer to use diplomatic and economic pressure to persuade Iran to abandon its program, but he has refused to rule out a military strike.

Bush and Olmert were also expected to use their meeting to renew their support for the Israeli-Palestinian peace talks, which were launched at a US-hosted international conference last November.

The talks have made very little visible progress and both sides have admitted that they will not meet their declared goal of inking a peace deal before Bush leaves office.

Little substantive movement is expected in the talks in the coming months as Israel heads for elections and the Palestinians remain deeply divided between Western-backed president Mahmud Abbas and the Islamist Hamas movement.