Arab League members  may now arm rebels fighting Syria's Assad regime, the group said as it offered a rebel coalition the league seat Damascus once occupied.
The 22-member Arab bloc said member states were free to offer military support to rebels  fighting the forces loyal to President Bashar Assad if they wished.
The league ministers meeting in Cairo stressed the right of each state according to its wishes to offer all types of self-defense, including military, to support the resilience of the Syrian people and the Free [Syrian] Army, the league said in a statement.
The league earlier supported only humanitarian aid and diplomacy.
League Secretary-General Nabil al-Araby said Wednesday the ministers invited the Syrian National Coalition, an opposition umbrella group backed by the West and Arab states, to attend the league summit in Doah, Qatar, March 26-27.
The umbrella group, founded in Doha in November 2012, would retain Syria's seat in the 22-member organization until elections [lead] to the formation of a government to assume the responsibilities of power in Syria, the league said.
Iraq and Algeria expressed reservations, while Lebanon declined to be part of the resolution, al-Araby told reporters.
Those three countries have refused to go along with the rest of the league, which in November recognized the coalition as the legitimate representative and main interlocutor with the Arab League.
Coalition spokesman Walid al-Bunni told al-Jazeera the decision was the most important step taken by the league since the civil war that has cost an estimated 70,000 lives began two years ago.
"We're very happy to hear that. It's late but it's very good," he said from the Hungarian capital, Budapest.
The league suspended Syria's membership in November 2011 after the Assad regime failed to abide by an Arab peace plan that sought to end the conflict.
Damascus had no immediate comment on the league's actions.
The actions came as insurgent fighters linked to the Syrian opposition seized 21 U.N. peacekeepers from the Philippines in the disputed Golan Heights region between Syria and Israel and threatened to treat them as prisoners of war.
U.N. Secretary-General Ban Ki-moon condemned the attack and the Security Council demanded the peacekeepers' immediate release.
The peacekeepers were in a convoy of trucks near an evacuated observation post when they were taken by about 30 armed rebels, a U.N. spokeswoman said.
A group identifying itself as the Martyrs of Yarmouk claimed responsibility for the capture.
Yarmouk is a Damascus neighborhood that is home to Syria's largest Palestinian refugee community. It started as a refugee camp in 1957 and has recently been a focus of sectarian violence.