YANGON, Myanmar (CNN) -- Bodies continued to pile up in Myanmar as the first U.S. aircraft carrying relief supplies touched down Monday in the cyclone-ravaged country.
U.S. Air Force personnel load relief supplies into an aircraft at the Royal Thai Navy Air Base in Utapao.
The shipment arrived in a time of dire need in the country's poorest regions, where people have been reduced to pumping water from ponds filled with the dead.
The first airlift, a C-130 Hercules loaded with 28,000 pounds of supplies, including water, mosquito netting and blankets, landed in Myanmar about 2 p.m.
Two more U.S. Air Force planes are expected to arrive in Myanmar Tuesday with more humanitarian supplies. White House spokeswoman Dana Perino also announced Monday that the United States has offered Myanmar an additional $13 million in aid, bringing the total to $16.25 million.
Though the Myanmar government recently began allowing international aid to enter the country, it was unclear when that aid would reach villages in southern Myanmar.
The country's ruling military junta is distrustful of Western countries.
A CNN correspondent who is not being identified for his safety said he saw the country's militia delivering international aid in some bigger cities. But some southern villages seemed overlooked.
"They have no drinking water whatsoever," the correspondent said. "When you don't have drinking water and you are forced to drink out of puddles and drinking reservoirs contaminated by dead bodies... It is a very dire situation." Watch how rotting corpses line the riverbanks »
More than a week after the cyclone hit the south Asian country, getting relief there has been a daunting task for international aid agencies.
The Britain-based international aid agency Oxfam warns that without the proper relief -- particularly clean water -- nearly 1.5 million people could be affected by a wider humanitarian crisis. Watch a report on widespread death and destruction »
A refugee camp in Pyanpon township was operating with five latrines for 3,500 people, UNICEF said.
The shore along the Irrawaddy River Delta remains lined for miles with bloated corpses. In the village of Da Mya Kyaung, only four of the 200 homes were partially intact.
"When I saw the water coming, I just put my two nephews on my shoulders and ran," villager U Wen Say said.
His son and his son's family drowned. Of the 500 people who lived in the village, two-thirds were missing.
The United Nations estimates the death toll from Cyclone Nargis ranges from 63,000 to 100,000, well above the Myanmar government's estimate of about 28,000. Tens of thousands of people are missing. Watch survivors await relief supplies »
U.S. officials hope the relief flights that have been approved by the Myanmar junta will forge a relationship that will allow the United States to send in disaster experts.
"As of right now, visas for them have not been approved," White House spokesman Gordon Johndroe said. "So we'll keep on working on this. We hope this is the beginning of a long line of assistance from the United States to the people of Burma."
The military junta has said it will accept international aid but insisted it would distribute the supplies itself. Watch relief supplies trickle in to Myanmar »
U.N. Secretary-General Ban Ki-moon on Monday blasted Myanmar's government for impeding aid efforts, calling on the junta to "put its people's lives first."
"This is not about politics. It is about saving people's lives. There is absolutely no more time to lose," Ban said
Four U.S. Navy ships that are in the region for an annual military exercise can also help in the relief mission if the Myanmar government gives the go-ahead.
The United States does not recognize the military junta.
Washington has been a vocal critic of the junta, which maintained control of the country even after 1990, when an opposition political party won victory in democratic elections.
Debbie Stothard, head of the Southeast Asian human rights group ALTSEAN-Burma, said her organization has received reports of aid packages being distributed with the names of military leaders on the labels.
"There's people who are very concerned now that the reason the aid workers are being blocked is so that the military can deliver aid selectively and so that they can appropriate the aid and pretend it was from them in the first place," Stothard said.
The country's name was changed from Burma to Myanmar in 1989, but many who do not recognize the current government still use its former name.