Peace talks aimed at ending nearly four years of civil war in Yemen, described by the UN special envoy as an important milestone, have started in Sweden.
Martin Griffiths announced the signing of a prisoner swap deal that would see thousands of families reunited.
His team is working alongside delegations from the Yemeni government and the Houthi rebels to enable informal talks due to last a week.
The war has caused the world's worst humanitarian crisis in recent times.
Thousands of people have died in fighting and millions have been pushed to the brink of starvation.
Consultations are resuming for the first time since 2016. The last attempt at a negotiated peace collapsed in September when the Houthis failed to show up for talks in Geneva.
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