ASTANA/BEIRUT: The main powerbrokers in Syria’s nearly seven-year conflict were heading toward a second day of negotiations in Astana as uncertainty loomed Thursday over a Moscow-driven plan to quickly reach a political settlement. Chief Russian negotiator Aleksandr Lavrentyev told journalists that Russia was forging ahead with plans to host a “National Dialogue Congress” in the Black Sea resort of Sochi to accelerate discussions over a political deal that have sputtered in Geneva.

The United Nations’ special envoy for Syria, Staffan de Mistura, has refused to say if the U.N. will back a plan promoted by Syrian President Bashar Assad but viewed warily by opponents of his government.

Speaking after the first day of talks Thursday, Lavrentyev said “quite a lot of time” had been spent discussing the congress proposal at negotiations being brokered by Syria’s allies Russia and Iran, as well as by Turkey, which supports the rebels.

Lavrentyev added that the regime in Syria and opposition forces would have to “forget old grievances” if they were to move toward a political deal.

The Russian envoy said there was no reason for U.S. forces to remain in Syria and that Washington’s stated reasons for maintaining a military presence there were groundless.

The congress, he said, would be “a platform that offers the different representatives of Syrian society the opportunity to solve matters of political settlement that so far have not been [at talks] in Geneva.”

But de Mistura, who was meeting with Russian Foreign Minister Sergei Lavrov and Defense Minister Sergei Shoigu in Moscow Thursday, said peace talks should proceed “one step at a time” and refused to comment any further on the congress proposal.

De Mistura, who acknowledged that the recent round of U.N.-sponsored negotiations in Geneva this month “was not a good meeting,” is expected to attend the final day of talks Friday.

The Astana meeting comes after Russian President Vladimir Putin ordered a partial withdrawal of Russian forces in Syria during a surprise visit to the war-torn country last week.

Syria was also on the agenda as Putin spoke by telephone Thursday with Saudi Arabia’s King Salman, whose country has supported the Syrian rebels but also fiercely opposes Iran’s efforts to extend its influence in the country.

Moscow has spearheaded the rounds of talks in Astana, which began at the start of the year, as it tries to convert its game-changing military intervention in Syria into a negotiated settlement.

At the meeting with de Mistura in Moscow, Lavrov said the talks Friday would focus on which groups and individuals would be invited to the Sochi event.

Iran-linked Arabic channel Al-Alam quoted a source in Astana as saying that Russia prepared the list of invitees to the congress meeting in Sochi, adding that the list includes 1,490 people.

The source also said 23 Kurdish representatives were included in the list, however Russia is still waiting on Turkey to study the names.

Ankara has previously rejected of the participation of any Kurdish party in the Sochi conference.

A 20-member opposition delegation was attending the talks in Astana, along with representatives of the Syrian government and of Russia, Iran and Turkey.

Kremlin spokesman Dmitry Peskov said that at present there were “no dates” agreed for the proposed congress.

Opposition delegates have expressed worries that the proposed event could prove a distraction from the U.N. negotiations.

A fragile cease-fire brokered at the end of last year by Moscow and Ankara has been bolstered somewhat by the negotiations in Astana, where the most recent rounds of talks have focused on implementing four “de-escalation zones” to stem the fighting between government and rebels.

Diplomatic contacts between the main protagonists in the conflict have intensified in recent months, but there is no sign that Damascus and its opponents are any closer to a political settlement.