Syria's main opposition group Thursday insisted President Bashar Assad must go and rejected calls to join forces against ISIS militants as it met with Russia's foreign minister. The head of Syria's National Coalition Khaled Khoja held talks with top diplomat Sergey Lavrov as part of a fresh push by Russia to find a way out of the 4-year-old civil war that has cost some 240,000 lives. Moscow – one of Assad's few remaining backers – is pushing a plan for a broader grouping than the U.S.-led coalition fighting ISIS, to include Syria's government and its allies. But Khoja – in Moscow for his first talks since February 2014 – ruled out cooperating with Assad and reiterated demands that the strongman must leave before any transitional government can be set up. "Bashar Assad has no role in the future of Syria," Khoja said in an interview with the Interfax news agency translated into Russian. At the start of the meeting, Lavrov insisted that Russia was working with regional and international players to find a political solution to the crisis and stop Syria from becoming a "hotbed of terrorism." "The main thing now is that these interests translate into practical coordinated steps," Lavrov said. National Coalition representative Badr Jamous described the visit as "very good," Russian Interfax reported after the meeting. "There were many issues where we agreed with the Russian representatives," Jamous was quoted as saying. Saudi Foreign Minister Adel al-Jubeir – a key backer of the Syrian opposition – rejected calls to work with Assad against ISIS after a meeting with Lavrov in Moscow Tuesday. The spate of meetings is part of a broader diplomatic flurry that saw Lavrov sit down with Jubeir and U.S. Secretary of State John Kerry in Doha earlier this month. As part of the push, Lavrov is expected to meet with the head of a newer grouping of opposition figures known as the Cairo Conference Committee Friday. Russia's top Middle East envoy Wednesday met in Moscow with the head of the Syrian Kurdish Democratic Union Party (PYD) Saleh Muslim to discuss the mooted anti-ISIS coalition and attempts to unite Syria's splintered opposition. Syria's opposition and Western officials have hinted that Moscow's backing for Assad may be wavering, but Moscow insists it remains firmly behind the Syrian leader. Rockets hit several districts in Syria's coastal city of Latakia, a stronghold of Assad, Thursday, killing two civilians and wounding 13, the country's state-run news agency, SANA, reported. It said the rockets were fired by "terrorists" – a term Syrian authorities use to refer to all rebels fighting to topple Assad. Explosions are rare in Latakia, which has remained relatively sidelined in the country's civil war. Syrian opposition groups also reported the Latakia attack though there were no further details. The city has been tense following the alleged fatal shooting of a senior military officer by Suleiman Assad, a relative of the president, over a road rage incident last week. Around 1,000 rallied this week, demanding the execution of Suleiman, who was arrested Tuesday. Meanwhile, a two-day cease-fire between Hezbollah fighters and rebel groups in the northern town of Zabadani, as well as in Foua and Kfarya, two Shiite villages in Idlib province, was extended for another 48 hours Thursday. Syrian forces have dropped more than 2,000 barrel bombs across the country since July, killing hundreds of people, the U.S. ambassador to the United Nations said Thursday. U.S. envoy Samantha Power called for action to end the use of a type of improvised explosive that has particularly been targeted at the Damascus suburb of Daraya and the southwest region of Zabadani. "The Assad regime has apparently grown reliant on the repugnant use of barrel bombs as an instrument of terror against innocent Syrian civilians," Power said in a statement. "It is long past time for the international community to come together to end the deplorable use of barrel bombs and all other forms of attacks against civilians in Syria." The U.S., France and Britain have repeatedly accused Assad's forces of using helicopters to drop barrels rigged with explosives on civilian areas. Power condemned the latest wave of indiscriminate bombings that have "killed hundreds of people and destroyed schools, mosques, markets, hospitals and ambulances". The U.N. Security Council is discussing proposals for a resolution on barrel bombs that would increase the pressure on Damascus even though it adopted a resolution in February last year demanding an end to the attacks. The government dropped barrel bombs across Deraa and Idlib provinces Thursday, the Syrian Observatory for Human Rights – a pro-opposition monitoring group said, not mentioning casualties.