The U.N.'s Yemen envoy Martin Griffiths landed at Sanaa international airport Monday for talks with Houthi rebels ahead of planned peace talks in Sweden this month.
An AFP photographer at the airport said Griffiths did not take questions on arrival.
Fifty wounded Houthis will also be evacuated from rebel-held Sanaa for medical treatment Monday, the Arab coalition allied with Yemen's government announced.
The evacuation on a U.N. chartered plane marks a key step in kickstarting stalled negotiations, as world powers press for an end to the four-year conflict that has pushed Yemen to the brink of famine.
The plane will transport 50 rebels, 50 "escorts," three Yemeni doctors and one U.N. doctor to the Omani capital Muscat.
International pressure has mounted in recent weeks to reach a breakthrough in the Yemen war, which pits the Iran-backed Houthis against the coalition.
War coupled with economic collapse has put nearly 14 million Yemenis -- half the country's population -- at risk of famine, according to U.N. agencies.
The World Health Organization estimates nearly 10,000 people have been killed since Saudi Arabia and its allies joined the Yemen war in 2015, aiming to bolster government's standing.
Rights groups fear the toll could be much higher.
Source: National News Agency