The USS George Washington aircraft carrier should arrive in 48 to 72 hours, the Pentagon said, confirming a Reuters report.
A statement said crew from the George Washington, which carries some 5,000 sailors and more than 80 aircraft, were being recalled early from shore leave in Hong Kong and the ship was expected to be under way in the coming hours. Other U.S. Navy ships would also head to the Philippines, it said.
Philippine officials have been overwhelmed by the scale of Typhoon Haiyan, one of the strongest on record, which tore a path through islands in the central Philippines on Friday.
About 660,000 people have been displaced and many have no access to food, water or medicine, the United Nations said.
Rescue workers were trying to reach towns and villages on Tuesday that have been cut off, which could reveal the full extent of the loss of life and devastation from the disaster.
The arrival of the U.S. carrier and its aircraft will accelerate the distribution of aid and ensure more injured survivors can be evacuated.
Another U.S. aircraft carrier, the USS Abraham Lincoln, led a massive aid operation off Indonesia's Aceh province in the wake of the Indian Ocean tsunami in 2004.
Britain is also sending a navy warship with equipment to make drinking water from seawater and a military transport aircraft, Prime Minister David Cameron said.
Officials in Tacloban, which bore the brunt of the storm, have said the death toll could be 10,000 in their city. There is grave concern for regions outside Tacloban.
"I think what worries us the most is that there are so many areas where we have no information from, and when we have this silence, it usually means the damage is even worse," Joseph Curry of the U.S. organization Catholic Relief Services, told NBC's "Today" program, speaking from Manila.
John Ging, director of operations at the U.N. Office for the Coordination of Humanitarian Affairs, said "many places are strewn with dead bodies" that need to be buried quickly to prevent the outbreak of a public health disaster.
"We're sadly expecting the worst as we get more and more access," Ging told reporters at the United Nations in New York.
President Benigno Aquino declared a state of national calamity and deployed hundreds of soldiers in Tacloban to quell looting. Tacloban's administration appeared to be in disarray as city and hospital workers focused on saving their own families and securing food.
Two Philippine Air Force C 130 cargo planes landed at Tacloban airport early on Tuesday, but unloaded more soldiers than relief supplies. Among dozens of troops was a unit of Special Forces, underscoring concerns about civil disorder in a city where little aid has been distributed.
The Special Forces immediately deployed at the airport to hold back angry and desperate families waiting in heavy rain in the hope of boarding the planes returning to Manila.
"Get back! Get back in the building!" shouted air force officials through megaphones, gesturing the crowds back inside the wrecked terminal. Many had walked for hours from their destroyed homes in the once-vibrant port city of 220,000, carrying meager possessions.
The sick, infants and the elderly were taken on board first. Pale-faced infants were passed over the crowd and carried on with several injured people. Many people wept and begged officials to let them on.
Aid trucks have struggled to enter the corpse-choked city because of the stream of people and vehicles leaving.
Reuters journalists travelled into Tacloban on a government aid truck late on Monday which was guarded by soldiers with assault rifles.
"It's risky," said Jewel Ray Marcia, an army lieutenant. "People are angry. They are going out of their minds."
Residents have told terrifying accounts of being swept away by a wall of water, revealing a city that had been hopelessly unprepared for a storm of Haiyan's power.
Most of the damage and deaths were caused by waves that inundated towns, washed ships ashore and swept away villages.
International relief efforts have begun to gather pace, with dozens of countries and organizations pledging tens of millions of dollars in aid.
Operations have been hampered because roads, airports and bridges were destroyed or covered in wreckage by surging waves and winds of 314 kph (195 mph).
U.N. aid chief Valerie Amos, who is travelling to the Philippines, released $25 million for aid relief on Monday from the U.N. Central Emergency Response Fund.
Amos and the Philippines government are due to launch an appeal and action plan on Tuesday to deal with the disaster.
Aquino's declaration of a state of national calamity will allow the government to use state funds for relief and to control prices. He said the government had set aside 18.7 billion pesos ($432.97 million) for rehabilitation.
Additional U.S. military forces also arrived in the Philippines on Monday to bolster relief efforts, officials said, with U.S. military cargo planes transporting food, medical supplies and water for victims.
Rescuers have yet to reach remote parts of the coast, such as Guiuan, a town in eastern Samar province with a population of 40,000 that was largely destroyed.
The typhoon also leveled Basey, a seaside town in Samar province about 10 km (6 miles) across a bay from Tacloban in Leyte province. About 2,000 people were missing in Basey, said the governor of Samar province.
The damage to the coconut- and rice-growing region was expected to amount to more than 3 billion pesos ($69 million), Citi Research said in a report, with "massive losses" for private property.
Typhoon Hagupit weakened to a tropical storm as it churned close to the Philippine capital on Monday, after killing 27 people on the eastern island of Samar island where it flattened homes, toppled trees and cut power and communications.
8 years ago
TANAUAN, the Philippines — For Teoderico Canales and her family, survival after Typhoon Haiyan has literally meant living in a pigsty. Their only water comes from a pump next to a small river where many people drowned.
9 years ago