People are growing increasingly desperate for food, water and medical supplies in typhoon-hit parts of the Philippines, a congressman has warned.
Martin Romualdez, from badly-hit Leyte, said a greater sense of urgency was needed to get aid to those in need.
The UN says more than 11 million people may have been affected and some 673,000 displaced by Typhoon Haiyan.
But on Tuesday, Philippine President Benigno Aquino said the death toll may be lower than first thought.
Speaking to CNN, he said the widely reported figure of 10,000 killed was "too high" and the figure was more likely up to 2,500.
The larger estimate had come from a police officer and local official and may have arisen from the "emotional trauma" of being at the centre of the disaster, Mr Aquino said.
But he said 29 municipalities had yet to be contacted to establish the number of victims there.
The National Disaster Risk Reduction and Management Council (NDRRMC) has put the official death toll at 1,833, as of 06:00 local time (22:00 GMT) on Wednesday. The number of injured stands at 2,623 with 84 listed as missing.
Relief operations are being stepped up, but many are still without aid, with damage to transport links and bad weather hindering distribution.
Tacloban - a city of 220,000 on Leyte island - is particularly badly affected, and correspondents say residents are becoming angry at the lack of progress and increasing breakdown in security.
Eight people died on Tuesday as desperate survivors mobbed a government rice warehouse in Alangalang, Leyte, officials said.
"One wall of our warehouses collapsed and eight people were crushed and killed instantly," Rex Estoperez, spokesman for the National Food Authority, said.
The police and soldiers were unable to stop the looters, who took more than 100,000 sacks of rice, Mr Estoperez added.
Martin Romualdez told the BBC that the "sense of urgency should be stepped up at the national level as the international relief organisations come in".
"And better co-ordination is needed, because we are seeing a lot of relief goods, medicines, equipment, coming in, but it's not reaching the people affected, thereby causing a sense of hopelessness and desperation in many of those who have survived and are now fleeing their homes, their municipalities, their locales, out of sheer desperation."
He said the damage to the city of Tacloban was immense.
"The destruction is so massive in scale and so extensive in our areas that we literally would have to rebuild from scratch. We just imagine it, our area, as a ground zero, as if a nuclear bomb had exploded above us."
Philippine armed forces spokesman Ramon Zagala told the BBC teams were struggling to reach isolated places.
"The area is very vast and the number of helicopters, although we have a lot of helicopters at the moment, it's really a challenge for us to bring [aid] to all the places and [bring] the number of goods that are needed."
But Philippine Interior Minister Mar Roxas told the BBC that relief efforts were on track.
"Our first priorities were, number one, to establish law and order; number two, to bring food and water to the people; and, number three, to recover the cadaver bags," he said.
"[Now] law and order has been stabilised, the supply of food and water is beginning - I'm not saying that we're anywhere near it - [but it] is beginning to be stabilised... and now we are concentrating on recovery of cadavers as well as on the distribution of the food and the relief that is coming in."
On Tuesday the UN launched an appeal for $301m (£190m) to help survivors. It has already released $25m to meet immediate needs.
The UN Office for the Co-ordination of Humanitarian Affairs (OCHA) says 11.3 million people are in need of vital goods and services, because of factors such as lack of food, healthcare and access to education and livelihoods.
US and British navy vessels are also heading to the Philippines and several nations have pledged millions of dollars in aid.
