The leader of the militant Hezbollah group warned Israel on Friday that plans by Jewish extremists to attack Jerusalem's most sensitive holy site would trigger an Arab and Muslim response.

Sheik Hassan Nasrallah urged Arab and Muslim peoples and governments to act to stop any possible attack by Jewish extremists on the disputed holy site on Sunday.

"Today, we face a serious threat to the Al Aqsa Mosque," Nasrallah told a Hezbollah rally in south Beirut.

"The one billion and 400 million Muslims must make the Zionist enemy expect that such an attack on the Al Aqsa Mosque will not remain without response," he said without elaborating.

"The Al Aqsa Mosque issue exceeds all national considerations ... It is an issue linked to the religion of Muslims, the doctrine of Muslims and the holy sites of Muslims. It exceeds all limits, laws and constraints."

Nasrallah's remarks came shortly after tens of thousands of members of the militant Palestinian group Hamas paraded through downtown Gaza City after Friday prayers, threatening to end a monthlong truce if Jewish extremists follow through on a pledge to hold a rally at the holy site.

Nasrallah warned Christians that their holy sites in Jerusalem faced the same threat.

"All of us know that the Zionists in Palestine do not recognize Jesus Christ, he said. "Therefore, we say that Christian holy sites are also threatened in Palestine. As such, we cannot be lenient on this matter."

Tens of thousands of Muslim worshippers concluded weekly prayers on the Temple Mount in Jerusalem on Friday without incident, Israel Radio reported.

Only Muslim men aged 40 and above holding Israeli ID cards were allowed to attend the prayers. There were be no limitations for women.

The police will remain on high alert in expectation of possible violence on Sunday at the site as well as in the streets of Jerusalem's Old City.

The Palestinians could participate in acts of protest and violent counter-demonstrations during prayers, because of the decision by the Revava movement to bring thousands of Jews to the site on Sunday, according to a senior intelligence source.

"We have very firm intelligence information that the Palestinians view the Revava movement's intentions as a threat to the Temple Mount, and they could conduct a violent counter-protest," the source said. "We have tried to take steps over the past few days to soothe the Muslim population, but we haven't been too successful."

He added that "the Temple Mount is like an explosive device that could be set off by the slightest confrontation."

The police have also expressed opposition to a plan by right-wing Knesset members, headed by Uri Ariel (National Union), to visit the Mount, saying it could be interpreted in the same context as the September 2000 visit by Ariel Sharon, which triggered the second intifada.

Asked if he would go without approval, Ariel replied: "We haven't decided at this point to fight with police. We think the Temple Mount should be open to Jews, and that there shouldn't be this disgraceful situation where only Arabs who threaten police and the state of Israel can go there."

United Arab List MK Abdulmalik Dehamshe said he would personally block the access of any Jews who tried to enter the Temple Mount compound Sunday. I am willing to become a martyr and die protecting the holy mosque, Dehamshe added.

The police, in consultation with the Shin Bet security service, have decided to bar entry to all Jews to the Temple Mount on Sunday. The warning level about a possible attack by Jewish extremists was raised from seven to eight, out of a maximum of 10.

Some 3,000 policemen will be deployed in the area of the Temple Mount and the Old City to prevent clashes. Police reinforcements have been sent to the capital from all over the country.

Police officers met with Waqf officials over the past few days and also talked with public figures in East Jerusalem in an effort to calm the atmosphere.

"The right-wing attempts to enter the Temple Mount are a provocation. At the same time, they are trying to tire out the police and security forces. This is a kind of general rehearsal for the disengagement plan," a senior source said Thursday.

Revava leader David Ha'Ivri said Thursday that the movement had tried to coordinate the visit with the police. He said the plan was to be accompanied by rabbis and guides so that Jews would not enter areas forbidden to them by halakha.

In view of the police refusal to let them enter the site, the protesters will gather below the Mount on Sunday morning "in order to show our demand for freedom of worship by Jews at the site," he said. "We do not plan to clash with the police or to create disorder. I therefore call on the participants to avoid friction."

The Palestinian parliament Thursday issued a warning to Israel about the consequences of any actions that could harm the Temple Mount, saying it was part of the government's plan "to Judaize and annex Jerusalem ... All responsibility will fall on the Israeli government," the statement warned.

Hamas on Thursday called on Palestinians everywhere to hold rallies after today's prayers, to protest against "the danger to the Al-Aqsa Mosque."

Nadav Shragai and Arnon Regular contributed to this report.