Aid workers have described the "unimaginable" devastation facing the typhoon-struck Philippines as they revealed the huge obstacles they must overcome to reach survivors.
The Disasters Emergency Committee (DEC), a group of 14 aid organisations, said that while life-saving aid was on the move, agencies were battling to overcome blocked roads, closed ports, an ill-equipped airport and increasing security concerns.
The disaster-ravaged country has become "increasingly volatile" as people become desperate for food and water, with some resorting to force, the DEC said.
Coree Steadmen, Christian Aid's emergency manager in the Philippines, said: "The devastation here is unimaginable. Aid workers are walking for hours and not seeing a single standing building.
"Most roads are covered with fallen trees and collapsed houses. Where roads are accessible, they are gridlocked with cars fleeing the area. Getting aid through is tough, but we are resourceful and we will find a way."
Hundreds of thousands of people have had their homes damaged or destroyed and are in desperate need of food, water and shelter – and concern has been raised specifically about the plight of women and girls.
The DEC said the biggest obstacle were blocked roads, which were narrow, strewn with heavy debris and in many cases impassable by vehicles.
Many aid workers are carrying out assessments on foot, walking for hours across rough terrain. One agency has sent mountain bikes to its team in Tacloban, one of the worst affected areas, to cross roads destroyed by landslides.
The airport in Tacloban is too small for aid agencies to fly in the volume of water, food and shelter materials needed and until Tuesday, sea ports had been closed or congested, the DEC said.
Aid planes are now being flown into Manila and Cebu, while a potential boat route is being considered.
Telephone lines and the internet had been offline for days, making contact with affected communities and Filipino partner agencies "impossible", it added.
To support UNICEF Ireland's Philippines Emergency Children's Appeal, visit www.unicef.ie or call lo-call 1850 767 999.
The Red Cross says more donations are urgently required – by phone at 1850 50 50 70 or online at redcross.ie.
Trocaire, who are also now operating in the Philippines, can receive donations online at www.trocaire.org/donate.
GOAL has dispatched an emergency response team, and can receive donations at 01 280 9779 or via the website www.goal.ie.