US Secretary of State John Kerry announced that he and his Russian counterpart Sergei Lavrov have reached a provisional agreement on terms of a cessation of hostilities in Syria, indicating there are still unresolved issues.
"We have reached a provisional agreement in principle on the terms of a cessation of hostilities that could begin in the coming days," Kerry told a news conference on Sunday in Amman with Jordanian Foreign Minister Nasser Judeh.
Kerry said he had spoken to Lavrov repeatedly, including a conversation earlier on Sunday, and he anticipated that US President Barack Obama and Russian President Vladimir Putin would be speaking in the coming days in order to complete the provisional agreement in principle.
The Russian Foreign Ministry also confirmed Lavrov and Kerry had spoken about conditions for a ceasefire in Syria on the telephone on Sunday.
It said discussions were on ceasefire conditions, which would exclude operations against organisations "recognised as terrorist by UN Security Council."
Syrian regime leader Bashar al Assad said on Saturday that he was ready for a ceasefire to end a five-year civil war, on condition "terrorists" did not use a lull in fighting to their advantage and that countries backing opposition forces halted support for them.
The Syrian opposition had earlier said it had agreed to the "possibility" of a temporary truce, provided there were guarantees regime's allies including Russia would cease fire, sieges were lifted and aid deliveries were allowed country-wide.
In Amman, Kerry additionally said the two sides are "filling out the details."
"The modalities for a cessation of hostilities are now being completed. In fact, we are closer to a ceasefire today than we have been," Kerry added.
Kerry was visiting the Jordanian capital for meetings with Judeh and King Abdullah for talks on the situation in the region.
He stated any deal would take a few days, while the two sides consulted with other countries and the Syrian opposition. Russia has to speak to the Syrian regime and Iran, and the United States has to speak to the Syrian opposition and its partners, Kerry said.
He declined to go into any details and said he did not expect an imminent change in the fighting on the ground.
"I do not believe that in the next few days, during which time we try to bring this into effect, there is somehow going to be a tipping point with respect to what is happening on the ground.... The opposition has made clear their determination to fight back," Kerry underlined.