The two-day meeting of the league's environment ministers was set for Monday. But the Libyans "apologised at the last minute and told the Arab League they could not host the forum", an unnamed league source told AFP on Monday.
The meeting was instead held at the organisation's headquarters in Cairo, but no Libyan representative took part, league sources said.
The Libyan authorities did not explain why they cancelled the summit which they had requested during the last meeting of Arab environment ministers held in Egypt in October 2002.
An Arab diplomat said Libya's attitude was linked to its decision to stop taking part in Arab ministerial meetings since the beginning of the year.
Libya still maintains a delegate at the Arab League, a voluntary body of 22 member states, including Palestine, dedicated to fostering cultural, economic and political cooperation.
In October 2002, Tripoli announced its withdrawal from the Arab League to protest at the absence of initiatives to the Iraqi and Palestinian crises, but it decided to suspend its decision after several Arab countries intervened.
In October this year, however, Libyan leader Muammar al-Qadhafi called on the Popular Congress, the basic structure of the Libyan political system, to "confirm Libya's withdrawal from the Arab League.
"The Arab League is in the middle of giving up the ghost, and Arabs will never be strong even if they unite... They will remain content every night to watch bloody newsreels from Palestine and Iraq," he said.