ADEN (Reuters) - Yemen s national airline said on Sunday it still lacks the security permits needed to resume commercial flights, a day after the transport minister said some flights would be allowed as a nationwide blockade is eased. The Saudi-led military coalition fighting against Yemen s Houthi movement said last week that it had closed all air, land and sea ports in Yemen to stem the alleged flow of arms to the Houthis from Iran. The move came after Saudi Arabia intercepted a missile fired towards Riyadh, which it blamed on Tehran.     Transport Minister Mourad al-Halimi had said Yemenia flights to the pro-Saudi government-held cities of Aden and Seiyun would resume on Sunday, but the national carrier said in a statement that it  didn t acquire the necessary permits  to fly. The United Nations had warned the total blockade could cause famine in the impoverished country where war has killed at least 10,000 people in the last 2-1/2 years and the United Nations Population Fund (UNFPA) expressed more concerns on Sunday. It urged in a statement that humanitarian aid be allowed to enter the country immediately, as Yemen has registered one of the highest rates in postpartum deaths. The government-held southern Yemeni port of Aden was reopened on Wednesday, but ports in Houthi-held areas are still shut. The coalition reopened the al Wadea border crossing linking Saudi Arabia with territory in eastern Yemen on Thursday. 