US Secretary of State John Kerry (left) and his Russian counterpart Sergei Lavrov in Moscow on May 7, 2013.

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Story highlights

Activist says Hezbollah fighters shot and killed civilians fleeing town

In other fighting, a jihadist leader was injured

Lavrov and Kerry say they will seek to convene a conference

Brahimi calls their statements "a significant step forward"

CNN  — 

The U.N. and Arab League point man on Syria praised the top U.S. and Russian diplomats Wednesday for their latest efforts to forge a solution to the Syrian conflict.

Lakhdar Brahimi called remarks from Russian Foreign Minister Sergey Lavrov and U.S. Secretary of State John Kerry “the first hopeful news concerning that unhappy country in a very long time.”

Speaking at a joint news conference Tuesday in Moscow, Kerry said he and Lavrov had agreed “as soon as is practicable, possibly and hopefully, by the end of this month” to “seek to convene an international conference.”

The aim would be to implement last summer’s Geneva communique brokered by Russia and the United States outlining how a transitional government could be formed.

If the conference takes place, it would be the first to bring together representatives of the warring sides, which have been unable to negotiate a settlement to the two-year conflict that has claimed more than 70,000 lives.

The opposition has adamantly refused any role for Syrian President Bashar al-Assad in any transitional government. But Lavrov, without naming al-Assad, said he is “not interested in the fate of certain persons.”

Kerry went further by telling reporters that “it’s impossible for me, as an individual, to understand how Syria could be governed in the future by the man who has committed the things we know have taken place.”

“But I’m not going to decide that tonight. I’m not going to decide that in the end. Because the Geneva communique says that the transitional government has to be chosen by mutual consent by the parties … the current regime and the opposition,” Kerry said.

Brahimi said he has urged the United States and Russia “to exercise leadership and work together to initiate a process to implement” the June 30 Geneva declaration.

“The statements made in Moscow constitute a very significant first step forward. It is nevertheless only a first step,” Brahimi said in a prepared statement. “There is every reason to expect the three other permanent members of the Security Council as a whole and indeed all the Security Council members to work together amongst themselves and with the secretary-general to carry the process forward.”

Deaths continue to mount, as 112 people were killed across Syria Wednesday, the opposition Local Coordination Committees said, including 30 in the Qusair area of Homs, in what the group said was a “massacre by Lebanese Hezbollah forces.”

A Syrian activist in Qusair who spoke with eight survivors of the attack said that Hezbollah fighters attacked civilian vehicles that were trying to flee the city.

Activist Hadi Albadalla said the Syrian regime and Hezbollah have had Qusair under siege for 20 days. Residents have witnessed increased shelling and tank artillery fire, Albadalla said.

The victims were trying to flee in four vehicles when they were spotted by Hezbollah militants and fired upon, Albadalla said. Many of those who escaped were found and killed, he said.

In other fighting Wednesday, the leader for the hardline jihadist group al-Nusra Front, Abu Mohammed al-Joulani, was injured during shelling in a southern suburb of Damascus, the London based activist group, Syrian Observatory for Human Rights, said. An activist in the area told the group that several members of the al-Nusra Front were also injured in the shelling which targeted them. The U.S. State Department designates the al-Nusra Front rebel group as a terror organization linked to al Qaeda in Iraq.

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CNN’s Joe Sterling, Amir Ahmed and Jill Dougherty contributed to this report