The UN security council has unanimously agreed a resolution endorsing an international roadmap for a peace process in Syria, a rare show of unity among major powers on a conflict that has claimed more than 250,000 lives. The resolution came after Russia and the US clinched a deal on a text. The two powers have had very different views on what should happen in Syria, where Islamic State militants control considerable territory.

The text called for the UN to present the council with options for monitoring a ceasefire within one month of adoption of the resolution. It also backed a timeline previously agreed in Vienna for talks between the government on a unity government and opposition, and eventual elections. The talks between Syria’s government and opposition should begin in early January, the resolution said. It also endorsed the continued battle to defeat Isis.

Foreign ministers met for more than five hours to discuss how to implement their call in Vienna last month for a ceasefire and the start of negotiations between the government and opposition in early January. At the same time, diplomats worked to overcome divisions on the text of the resolution.

US’ John Kerry said the resulting agreement gives the Syrian people a real choice, not between Assad and Daesh, but between war and peace.