The newly appointed UN envoy to Yemen arrived in the rebel-held capital Sanaa on Tuesday, hours before the scheduled start of a five-day ceasefire, an airport official said.

Mauritanian diplomat Ismail Ould Cheikh Ahmed, who was appointed in late April, toured Gulf countries that have waged a more than six week air war against the rebels before travelling to Sanaa.

The ceasefire was scheduled to enter effect at 11:00 pm (2000 GMT).