During a press briefing on September 9, Lavrov described the agreement as a "significant, practical and concrete" package, comprising five documents that will not be made public since they contain "rather sensitive and serious information."
The US made a number of concessions to Russia during the talks. The reason is the latest success of the Syrian Army in Aleppo, Viktor Sergeyev, professor of political science at the Moscow State Institute of International Relations, said.
"Washington delayed this agreement during the recent six months. This US acquiescence was prompted by the breakthrough by Syrian forces in Aleppo," he told RIA Novosti.
Lavrov added that the top priority for this agreement is to reconfirm the ceasefire, stressing that both the US and Russia will work will with all parties to ensure that hostilities cease within the next 48 hours.
"Recently, combat actions have been focused on Aleppo. The recent advances of the Syrian Army prove that the war is nearing its end. If the army takes full control over Aleppo it will be almost over. In the north, in Raqqa, there are US-backed Kurdish forces. Of course, destroying Daesh militants in Raqqa will take some time, but there will no problem with that," the expert said.
He added that the next issue to address should be resumption of the intra-Syrian talks, which should include all opposition groups.
"The participation of opposition groups in the talks is possible. The question is whether they would be able to come to an agreement," Sergeyev noted.
The expert also underscored that after if Washington pressures the opposition the ceasefire will work.
Another major problem is Syrian President Bashar Assad and his role in country’s future. The West and opposition insist that Assad must go but in Syria there is no other politician able to control the situation.
"The Assad problem remains. It can’t be ruled out that he will have to resign. But it’s still unclear who can replace him. If there is no proper candidate to replace Assad the situation won’t improve," Sergeyev said.
The expert suggested that during the talks Russia’s main goal would be to keep Assad in any role because now he is the only who can more or less control the situation.