Col Gaddafi has threatened to pull Libya out of the Arab League

The gesture was a further blow to the Tunis meeting, which was cancelled in March amid disagreements over reforms.

"Libya sees itself forced to boycott the summit because it does not agree with the agenda," Col Gaddafi said.

The Arab League meeting is due to discuss the occupation of Iraq - including prisoner abuse - as well as the Israeli-Palestinian conflict.

Several absent

Col Gaddafi walked out of the conference hall in Tunis during a speech by Arab League Secretary-General Amr Moussa.

Libya sees itself forced to boycott the summit because it does not agree with the agenda Colonel Gaddafi Crisis in Arab world Arab press warns summit

Diplomats said Mr Gaddafi was apparently annoyed by Mr Moussa's criticism of Arabs who act unilaterally - an apparent reference to Libya's decision to scrap programmes to develop weapons of mass destruction.

Mr Gaddafi criticised the peace initiatives touted by some Arab leaders, saying the return of Palestinian land and refugees should be non-negotiable.

He has often threatened to pull Libya out of the Arab League, and had to be urged by fellow leaders to attend this summit to help show unity.

There were kings, emirs, presidents and prime ministers in the audience on Saturday, but several Arab leaders decided not to make the trip.

The Arab League has prepared draft resolutions for the summit covering the major Middle East issues.

One expressed outrage over the abuse of Iraqi prisoners in US custody.

Others called for peace between Israel and the Palestinians, condemned terrorism, and advocated political and economic reform in Arab nations.

Arab leaders came to show unity - but not all were there

Opening the summit, Tunisian President Zine El Abidine Ben Ali asked delegates to stand in silence in memory of the Palestinian victims of Israeli attacks.

He also called for Iraq to be given its sovereignty "as soon as possible".

Palestinian leader Yasser Arafat, under Israeli siege in his West Bank headquarters, had to speak via videophone for the third year running.

He accused Israel of waging a "war of annihilation", but said Palestinians would still work for peace.