The Red Cross says it is extremely concerned by the destruction of the runway at Sana'a airport in airstrikes by a Saudi-led coalition targeting Yemeni rebels.
The airport was "an essential civilian infrastructure and the main lifeline to supply essential humanitarian goods and services", the international humanitarian organisation said.
Issued jointly with Medecins sans Frontieres, the statement on Monday is unusually harshly worded for the International Committee of the Red Cross, which observes a policy of strict neutrality.
It comes amid growing alarm among relief organisations over the impact of the conflict on one of the poorest countries in the Arab world.
The two organisations called for "robust and unobstructed channels" for humanitarian supplies to be opened and respected by all parties to the conflict.
"The harsh restrictions on importations imposed by the coalition for the past six weeks, added to the extreme fuel shortages, have made the daily lives of Yemenis unbearable and their suffering immense," said Cedric Schweizer, head of the ICRC team in Yemen.
Yemen relies on imports for 80 to 100 per cent of key foodstuffs, according to Britain-based charity Oxfam.
Saudi Arabia and Arab allies have been carrying out airstrikes against the mainly Shi'ite Houthi rebels since they advanced in March on the southern city of Aden, forcing President Abd Rabu Mansour Hadi to flee the country.
Aden saw advances Monday for local anti-Houthi fighters, who wrested full control of the city's airport from the rebels and allied military units, residents and local journalists told dpa.
The local militias' gains raise the prospect of possible aid flights and military supplies to Yemen's beleaguered second city.
The airport is strategically important as it extends almost all the way across the narrow strip of land connecting mainland Aden with the city's port and older residential districts on a volcanic peninsula.
An alliance of pro-Hadi militias and secessionist fighters has been battling to fend off Houthi advances into formerly independent southern Yemen since March. The rebels have met resistance from local fighters and tribesmen in central and eastern Yemen.
The Houthis, whose power base is in the tribal far north, seized control of the capital Sana'a in September.
