The U.N. World Food Program says it will begin to airlift food to the drought-stricken Horn of Africa on Wednesday.

WFP director Josette Sheeran told VOA Tuesday the first flights will head to Somalia's capital, Mogadishu. The airlift was scheduled to begin Tuesday, but the flights were held up by logistical problems in Kenya.

The WFP had said Monday planes will carry food to Mogadishu, eastern Ethiopia, and northern Kenya, near the Somali border. Sheeran said the U.N. agency is calling in resources and personnel from other parts of the world to respond to the crisis.

U.N. and U.S. officials have said more than 11 million people are in need of emergency aid to survive.

In Somalia alone, Sheeran said about one-third of the population is facing starvation — and she said people tell of having to leave dying family members behind as they continue their long journeys in search of help.

Access to southern Somalia — where the U.N. formally declared a famine last week — has been hampered by the militant group al-Shabab. The group controls large sections of the region and has denied that a famine is taking place.

On Tuesday, the U.N. refugee agency said 100,000 Somalis have arrived at Mogadishu-area camps in the past two months, and continue to come at a rate of 1,000 per day.

It says hundreds of thousands of others have fled to camps in neighboring Kenya and Ethiopia.

The U.N. is planning a donors' conference Wednesday in Kenya's capital, Nairobi. The international body says “massive” action is needed to help the drought victims, many of whom are children. It is seeking pledges of $1.6 billion.