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Syria's increasingly isolated president appealed on Wednesday to the leaders of a five-nation economic forum meeting in South Africa to help end his country's two-year conflict.

Bashar Assad's appeal came a day after the Arab League endorsed Syria's Western-backed opposition coalition, delivering another blow to the regime in Damascus.

Assad sent a letter urging the leaders of the five nation BRICS forum — Brazil, Russia, India, China and South Africa — to "work for an immediate cessation of violence that would guarantee the success of the political solution" in Syria. The World Bank says these countries are driving global economic growth.

"This requires a clear international will to dry up the sources of terrorism and stop its funding and arming," Assad said in the letter, which was carried by Syrian state media on Wednesday.

Assad said Syria is subjected to "acts of terrorism backed by Arab, regional and Western nations" — a reference to the Western-backed opposition fighting his regime.

Attempts to end Syria's crisis through peaceful means have so far failed to make progress. The opposition, including the main Syrian National Coalition, says it will accept nothing less than Assad's departure from power while his government has vowed to continue the battle until its troops crush the rebel forces.

On Tuesday, Syria's opposition for the first time took over the country's seat in the Arab League at a summit in Qatar in a diplomatic triumph by Assad's opponents.

The opposition's ascension to the League further demonstrated the extent of the regime's isolation two years into a ferocious civil war that the U.N. says has killed an estimated 70,000 people.

And in a further show of solidarity with anti-Assad forces, the summit in Qatar endorsed the "right of each state" to provide the Syrian people and the rebel Free Syrian Army with "all necessary means to ... defend themselves, including military means."

But the opposition alliance is marred by severe divisions among its ranks, and often disconnected from the rebel forces fighting inside Syria, so it's not immediately clear how the developments in Qatar would translate on the ground.

At the gathering in the South African resort of Durban, President Jacob Zuma and his Russian counterpart, Vladimir Putin, were asked Tuesday whether they would use their influence to persuade Assad to allow unimpeded U.N. humanitarian access across all Syria's borders, as leading activists from BRICS countries have asked for.

Zuma ignored the question while Putin, in a throwaway remark, said: "We will think about it." Earlier, the Russian president said the forum's leaders would jointly "work for a peaceful resolution to the Syrian crisis.

BRICS countries, including Assad's key ally Russia, oppose foreign intervention in Syria and accuse the West of trying to force regime change. Russia, China and South Africa have also voted against U.N. Security Council resolutions on Syria.

In his letter, Assad criticized European and U.S. sanctions imposed on his regime and urged BRICS leaders to "exert every possible effort to lift the suffering of the Syrian people that were caused by the sanctions."

He said the sanctions are "directly effecting the lives of our people," an apparent reference to shortages of goods and soaring prices.

In Syria, activist groups reported violence in different areas in the country on Wednesday, including Damascus and its suburbs and the southern Quneitra region along the cease-fire line separating Syria from Israeli-occupied Golan Heights.

The Britain-based Syrian Observatory for Human Rights and the Local Coordination Committees reported clashes and shelling in Quneitra villages of Bir Ajam, Rasm al-Hawa and Ein el-Darb. The Observatory said rebels overran three army posts near Bir Ajam on Wednesday.

The area near Golan Heights, a strategic goal of the rebels, has been the scene of heavy clashes for days.

The Observatory, which relies on a network of activists on the ground, also reported an air raid by Assad's air force on the town of Qusair near the border with Lebanon as well as aerial attacks on the Damascus neighborhood of Qaboun.

Syria's crisis began in March 2011 with protests demanding Assad's ouster. Following a harsh government crackdown, the uprising steadily grew more violent until it became a full-fledged civil war.