UK and US ships were heading to the Philippines as the UN appealed for aid amid the large-scale devastation caused by Typhoon Haiyan.
The US has deployed an aircraft carrier and navy ships to the Philippines, while the UK is sending a naval destroyer.
At least 10,000 people are feared to have been killed, and thousands of survivors desperately require aid.
Philippine President Benigno Aquino has declared a state of national calamity.
In a statement, Benigno Aquino said the two worst affected provinces, Leyte and Samar, had suffered massive destruction and loss of life.
A huge international relief effort is under way, but rescue workers have struggled to reach areas cut off since the storm.
UN Secretary General Ban Ki-moon described images of the impact of the storm as “heartbreaking”.
The UN would launch a large-scale humanitarian plan, and allocate $25 million “to fund critical relief efforts”, Ban Ki-moon said.
“Many thousands of people are reported to have died and almost 10 million people have been affected… Let us all show our solidarity with the people of the Philippines at this time of need,” he added.
One of the most powerful storms on record to make landfall, Typhoon Haiyan – named “Yolanda” by Philippine authorities – struck the coastal provinces of Leyte and Samar on Friday.
Typhoon Haiyan then headed west, sweeping through six central Philippine islands.
Air Force Capt Antonio Tamayo told AP news agency the scene in Tacloban, one of the worst-hit areas, was “overwhelming”.
“We need more medicine. We cannot give anti-tetanus vaccine shots because we have none.”
Officials said looting was widespread and order was proving difficult to enforce. Correspondents say many ordinary people are simply scavenging for the food and water needed to survive.
The government says it has deployed armored vehicles to Tacloban to deter looters.
“We are circulating [the vehicles] in the city to show the people, especially those with bad intentions, that the authorities have returned,” Interior Secretary Mar Roxas told DZMM radio.
In a statement, the US said that aircraft carrier USS George Washington and other navy ships should arrive in the Philippines “within 48-72 hours”.
“As needed, these ships and aircraft will be able to provide humanitarian assistance, supplies, and medical care in support of the ongoing efforts led by the government and military of the Republic of the Philippines,” the statement said.
UK Prime Minister David Cameron announced that the Royal Navy destroyer HMS Darling would soon head to the disaster zone from Singapore.
It would take five days to arrive but once in the Philippines would bring engineering and first aid expertise, as well as the use of a Lynx helicopter.
Other countries have also pledged millions of dollars in assistance. Japan is providing $10 million and Australia $9 million in humanitarian aid, while New Zealand has pledged over $1.5 million.
Reports from Tacloban say soldiers have been distributing food and water to some residents and the US military has sent marines to the city.
A Philippine military spokesman was quoted as saying on Monday that 942 people had died in the typhoon’s aftermath, though it is clear the official death toll will rise significantly.
UN humanitarian official John Ging said: “Many places are strewn with dead bodies.”
“The first priority of response teams, once they were able to navigate their way into these areas, is to mobilize the burial of dead bodies because of the public health issues,” he said.
“As we get more and more access we find the tragedy of more and more people killed in this typhoon,” he added.
- Australia: Aus$10 million ($9.4 million), including medical personnel
- China: $100,000
- European Commission: 3 million euros ($4 million)
- Indonesia: Aircraft, personnel, drinking water, food, generators, medicine
- Japan: $10 million, 25 emergency medical personnel
- New Zealand: NZ$2.15 million ($1.7 million)
- Taiwan: $200,000
- UK: £10 million ($15 million) non-food aid package
- UN: central emergency relief fund: $25 million
- US: At least 180 marines and sailors, transporter planes, emergency food, water, shelter and hygiene materials
- Vietnam: $100,000 [youtube Bq6xnwwvFAE 650]