A UN plane carrying desperately needed vaccines landed in rebel-held Sanaa on Saturday, three weeks after the Saudi-led coalition closed off access to the airport following a missile attack launched at Riyadh.
Three other aircraft — two carrying UN aid workers and one carrying International Committee of the Red Cross staff — also landed at the airport.
The UN humanitarian affairs office said on Friday it had been given clearance by the coalition to resume flights into the Yemeni capital.
But it added that desperately needed shipments of food and medicines to the rebel-held Red Sea port of Hodeidah remained blocked.
The coalition, which includes the UAE, is fighting Yemen's Houthi rebels on behalf of the internationally-recognised government. It closed Yemen's borders and shut access to its sea and air ports on November 6 in response to a missile attack launched by the Houthis that targeted Riyadh's international airport.
Since then, however, the coalition has begun lifting some restrictions and on Wednesday announced that it would provide access for aid to be delivered through the port at Hodeidah and Sanaa airport.
The UN children's agency, Unicef, said Saturday's flight was carrying more than 15 tonnes, or 1.9 million doses, of vaccine for diphtheria, tetanus and other preventable diseases.
The World Health Organisation confirmed earlier this week that diphtheria was spreading as children went unvaccinated and doctors in Hodeidah reported three deaths.
More than 2,000 people have died of cholera in Yemen this year.