Egypt offered the Red Sea resort of Sharm al-Shaikh to replace the Tunisian capital in hosting the gathering.
Musa said on Thursday there was consensus within the 22-member organisation "to hold a summit under the presidency of Tunisia".
Differences remained on the democratic reforms that erupted in the preparatory meetings of the cancelled summit, but he insisted these were no reason not to hold a rescheduled summit.
"There are differences on the extent of the reforms and the initiatives coming from outside," Musa said, referring to Washington's so-called "Greater Middle East Initiative" for political reforms.
"But only a summit can resolve these differences," he added, criticising as "very dangerous" Tunisia's decision to scrap the summit that to open on 29 March.
Musa is to travel to Tunis on Friday to try to find a compromise, as part of a trip that will also take him to Algiers and Rabat.
Tunisia cited the refusal of some Arab states to tackle the issue of democracy for its surprise decision to postpone the summit, a move that triggered dismay in Cairo and several Arab capitals.
In Tunis, four opposition parties issued a statement on Thursday disputing President Zain al-Abidin bin Ali pro-democracy claims.
Amr Musa (C) left Tunis in a hurry
with other Arab delegates
"The reasons cited for the postponement of the summit are in total contradiction with the state of freedoms and rights in Tunisia," said the groups, three of which are legal.
Egypt has lobbied Arab states to support Sharm al-Shaikh as the venue.
Egyptian President Husni Mubarak consulted on Wednesday with the de facto ruler of Saudi Arabia, Crown Prince Abd Allah bin Abd Al-Aziz, as well as with King Hamad of Bahrain and King Abd Allah II of Jordan.
But Mubarak's meetings with his Syrian and Sudanese counterparts, planned for Thursday, were postponed because of a "change in the schedules of the three presidents," said a senior Egyptian official.
Other dates will be arranged for the visit of Syria's Bashar al-Asad and Sudan's Umar al-Bashir, he added.
According to Egyptian officials, 10 of the 22 Arab League members have so far said they favour having the summit in Sharm al-Shaikh.
They were said to be Egypt, Saudi Arabia, Syria, Bahrain, Kuwait, Jordan, Yemen, the Palestinians, the United Arab Emirates and Iraq.
The Egyptian government daily al-Ahram said on Wednesday the rescheduled summit would be held in Egypt in early May, although Tunisia continues to insist on its right to host it.
The collapse of the summit in Tunis has also prompted widespread popular criticism that Arab leaders had failed to meet the challenge of standing up to Israel after the assassination last week of Hamas spiritual leader and founder Shaikh Ahmad Yasin.