Security will be a central concern for Jordan which hosts Wednesday a key summit aimed at relaunching the Palestinian-Israeli peace process, officials said.

"The presence of the US president and the Israeli prime minister calls for important security measures because of the threats that are regularly made against their countries by terrorist groups," one official said.

That is why the small but well-protected southern Red Sea coastal town of Aqaba was chosen over the Jordanian capital Amman to host the summit between Bush, Sharon and Israeli prime minister Mahmud Abbas.

"Aqaba is a free trade zone and has well-defined custom checkpoints. This will help to control all those who enter the town," the official said on condition of anonymity.

Jordan has beefed up security around Aqaba, with Jordanian intelligence officers working closely with US security agents in the run-up to Wednesday's summit, security sources said.

Draconian measures have been deployed around two five-star hotels overlooking the northern tip of the Red Sea that will host the US, Palestinian and Israeli delegations in Aqaba, where security agents in civilian clothes outnumber soldiers.

The summit itself will take place in the beachfront royal palace, where access is strictly banned even on normal days.

"The palace was built on the borders with Israel, as a symbol of security between Aqaba and Eilat," a Jordanian official said.

The royal residence was the venue of many secret meetings in the 1970s between the late King Hussein and Yitzhak Rabin, who later became Israel's prime minister until his assassination in 1995, a year after signing the Jordan-Israel peace treaty.

Despite threats from Osama bin Laden's terror network, Al-Qaeda, and a recent condemnation by his top deputy, Jordanian officials are confident that they can prevent any attack from taking place in the kingdom.

In a May 21 broadcast of an audiotape, bin Laden's deputy Ayman al-Zawahiri called for Muslims to launch new anti-western attacks and condemned several Arab nations, including Jordan, for assisting in the US-led war on Iraq.

"We are always vigilant and attentive concerning the security of our country and we will be more so as we prepare for this historic summit," the Jordanian official said.

Aqaba built a reputation for tight security during the troubled decades of the Middle East conflict, and was always a haven even during the 1967 and 1973 Arab-Israeli wars.

The coastal town is adjacent to the Israeli Red Sea resort of Eilat, which once belonged to Jordan and was known as Umm al-Rashrash, until Israel occupied it in 1950, two years after the creation of the Jewish state.

An unwritten agreement was later reached between Jordan and Israel guaranteeing that Aqaba and Eilat would be spared any military attack.

When Palestinian guerrillas used Jordan as a base to attack Israel from 1968 until 1970, Aqaba and Eilat continued to be spared, despite one incident in 1969 when rockets were fired on Eilat.

The shooting was considered a "mistake", brought quickly under control and Israel refrained from taking any action.