The United Nations Security Council has adopted a resolution welcoming a ceasefire in the Syrian civil war brokered by Russia and Turkey.
Russia and Turkey announced the ceasefire this week, the third truce this year seeking to end the nearly six years of war in Syria.
The resolution also welcomes plans for talks to take place in Astana, Kazakhstan between the Syrian government and the opposition, ahead of the resumption of UN-brokered talks in Geneva in February.
In remarks after the vote, several delegates on the Security Council welcomed the ceasefire but said the agreement contained grey areas and that its implementation was fragile.
The original Russian draft would have had the council endorse the deal, but after last minute negotiations the language was changed to welcome and support the deal to appease some council members and win unanimous support, diplomats said.
However, Syrian rebel groups have said they would consider the ceasefire "null and void" if Syrian government forces and their allies continued to violate it.
Russia, which supports Syrian President Bashar al-Assad, had urged the UN to give its blessing to the fragile ceasefire.
Clashes and air strikes have persisted in some areas since the ceasefire began yesterday, though the Syrian Observatory for Human Rights, a monitoring group, said today the truce was still largely holding.
"Continued violations by the regime and bombardment and attempts to attack areas under the control of the revolutionary factions will make the agreement null and void," a statement signed by a number of rebel groups said.
It said government forces and their allies had been trying to press advances, particularly in an area northwest of Damascus.
Russia and Turkey, which backs the armed opposition to Mr Assad, brokered the ceasefire agreement in the hope of preparing the way for peace talks in Kazakhstan in the new year.
In their statement, the rebels said it appeared the government and the opposition had signed two different versions of the ceasefire deal, one of which was missing "a number of key and essential points that are non-negotiable", but did not say what those were.
There has been confusion over which groups in the opposition are included in the ceasefire.
The so-called Islamic State, which has made enemies of all sides in the conflict, is not included.
The Syrian army said on Thursday the militant group formerly known as the Nusra Front was not part of the truce.
However, several rebel officials said the group, which has been renamed Jabhat Fateh al-Sham, was also included in the ceasefire deal.
