Top diplomats from 17 nations have resumed Vienna talks on the Syria conflict, hoping to reinvigorate a peace effort that has effectively collapsed.
US Secretary of State John Kerry and Russia's Foreign Minister Sergei Lavrov were chairing the meeting of the International Syria Support Group (ISSG) on Tuesday.
Powers attending the talks are Russia and Iran on the one hand, supporting Syrian President Bashar Assad, and the US, Saudi Arabia and European states on the other, trying to topple him with the help of militants.
Russia said Lavrov met Kerry ahead of the talks, discussing the need to cut off the supply routes benefiting terrorists “primarily those crossing the Syrian-Turkish border."
Lavrov also met Foreign Minister Mohammad Javad Zarif who said Iran supported the truce and a peace dialog, but warned that a silence of arms might aid terrorist groups operating in Syria.
"We should not allow terrorists to use the cessation of hostilities for further terror operations," Zarif said.
“Unfortunately there seems to be a persistence by some that they want to pursue a military solution, that illusion has to come to an end and they should look for a political solution," he added.
Saudi Arabia is one of the most aggressive supporters of militant groups, represented in negotiations by the High Negotiation Committee (HNC), which was organized by the kingdom itself.
Riyadh has repeatedly stated that Assad will eventually be removed by either diplomatic or military means.
Saudi Foreign Minister Adel al-Jubeir signaled that Riyadh is not pinning its hopes on the US convincing Russia to remove Assad and suggested a push to make sure militants were better armed might be needed.
"The choice is Bashar al-Assad's," he told reporters in Paris last week. "He will be removed, either through a political process or through military force."
Arab and western officials involved said they do not expect significant achievements from the talks.
According to Reuters, the Obama administration's failure to convince Moscow that Assad must go is fueling European frustration.
"Some diplomats and analysts question whether the United States has misread Russia's desire to keep Assad in power," the news agency said.
"The conventional wisdom regarding the current situation in Syria is that Russia is calling the shots and the US is working with it, despite the two countries’ ostensible disagreement about Assad’s fate," the British daily the Guardian said Tuesday.
UN-brokered peace talks in Geneva ended last month without any progress after the delegation of the opposition walked out, and declared a "new war" against the Syrian government.
German Foreign Minister Frank-Walter Steinmeier said Tuesday the foreign ministers were expected to explore ways to bring the opposition back to negotiations with the Assad government.
Steinmeier said the participants wanted to help strengthen the truce and improve aid efforts.
The Russian Defense Ministry said it delivered 1.5 tonnes of humanitarian aid for residents in Syria's Latakia province.
Syrian State Minister for National Reconciliation Affairs Ali Haidar, meanwhile, held a meeting with representatives from besieged areas, including Madaya, Fouaa and Kefraya.
They discussed the possibility of lifting the sieges by exchanging the control rights of the besieged areas in the name of national reconciliation.
In eastern Syria, however, media and local sources said three children and a woman had been killed in US airstrikes purportedly targeting Daesh terrorists.
The airstrikes hit al-Bukamal city in the province of Dayr al-Zawr near the border with Iraq on Monday, killing the four and inflicting heavy losses on properties.
Syrian army units repelled attacks by Daesh terrorists trying to seize high points near the central city of Palmyra. "The terrorists have sustained considerable losses," the Russian Defense Ministry said.