RAMALLAH, Dec 31 (Reuters) - Palestinian security forces loyal to President Mahmoud Abbas have arrested Hamas militants who were plotting a suicide bombing, Abbas's foreign and information minister said on Monday.

Riyad al-Malki told a news conference Palestinian security forces had arrested members of the Islamist group, but did not say whether the attack was planned for Israel or the West Bank or how many people had been arrested.

The announcement came a day after Israeli Prime Minister Ehud Olmert ruled out relaxing Israel's grip on the occupied West Bank until the Palestinians rein in militants.

Israel frequently says it has thwarted suicide bombings but it is rare for the Palestinians to make such an announcement.

Malki declined to say when the arrests took place but said security forces found a confessional video recorded by the would-be bombers. He also said officers had found mercury, which could be used to make explosive devices, in Nablus.

Olmert and Abbas agreed at a U.S.-sponsored peace conference last month in Annapolis, Maryland, to launch negotiations with the goal of reaching a statehood agreement by the end of 2008.

Olmert has said Israel will not implement any deal until the Palestinians meet their obligations under a "road map" peace plan to rein in militants in the West Bank and the Gaza Strip.

The Palestinians say Israel is not meeting its road map obligations on freezing settlement activity.

Hamas, which seized control of the Gaza Strip in June after clashes with its rival Fatah faction, has rejected Abbas's talks with the Jewish state and vowed to undermine the peace process.

Hamas spokesman Fawzi Barhoum declined to comment on whether its members were arrested, but said: "We support any act of resistance against the Israeli occupation but we will not be surprised if the government ... fabricates charges to pursue their arrest campaign against Hamas and other factions of resistance."

Abbas's government has deployed hundreds of security officers in West Bank towns in recent weeks as part of a Western-backed drive to crack down on gunmen and gangsters.

The Israeli police and army said they had not heard about any attacks that had been prevented by Abbas's forces. (Reporting by Mohammed Assadi; Additional reporting by Ali Sawafta; editing by Janet Lawrence)

AlertNet news is provided by