More food reached Myanmar's hungry cyclone victims Sunday as roads were cleared of fallen trees and debris, but there still was no sign the government would let foreign experts handle the aid distribution that the ruling military junta was accused of manipulating. "Visas for international humanitarian personnel remain a critical issue, and one on which the UN and Myanmar's regional partners are engaged," an internal report from the UN humanitarian coordinating agency said. The junta says it only wants international relief material and money - not the people to manage it. It wants to hand out all donated supplies on its own to an estimated 2 million people who are without food or shelter and face the threat of diseases following Cyclone Nargis, which battered the country on May 3. According to the government, 23,335 people died and 37,019 are missing. However, British aid group Oxfam has warned that the lives of up to 1.5 million cyclone victims are in danger from diseases if clean water and sanitation are not provided soon. Oxfam's regional chief Sarah Ireland says "there are all the factors" for a public health catastrophe. She says the death toll from the May 3 cyclone is likely to be 100,000 - and that number could eventually multiply by 15 times. She told reporters Sunday: "We are afraid there is a real risk of a massive public catastrophe waiting to happen in Myanmar. It is a perfect storm, if you will." Debbie Stothard, head of the Southeast Asian human rights group ALTSEAN-Burma, said the ruling generals were manipulating aid and delivering it selectively, ignoring the needy. Myanmar is also known as Burma. "Even in Yangon area, which is reachable by the regime, people are complaining they are not getting aid. What they are getting is rotting rice," she said, she told Associated Press Television News in Bangkok, Thailand. Packing enormously powerful winds, the storm battered the Irrawaddy delta. It left hundreds of villages under water, and felled trees and power lines. Myanmar's largest city, Yangon, was also badly hit. UN staff in Myanmar were reporting "significant progress in clearing roadways, and the piped water supply has been partially restored to some parts of Yangon city," the UN report said. It said helicopter loads of international aid arriving in Yangon were being relayed to Pathein for distribution in the Irrawaddy delta. "Aid is getting through in increased amounts," said the International Federation of Red Cross and Red Crescent Societies. It said three planes of the federation with 14 tons of shelter material arrived in Myanmar and were cleared without delay, replenishing Red Cross stocks already in the country before the cyclone. So far the humanitarian effort has supported 220,000 people, it said. A further seven flights were expected to arrive Monday, carrying 20 tons of shelter material, jerry cans and 2,000 mosquito nets. Myanmar's junta has also been criticized for holding a referendum on Saturday on a new constitution aimed at solidifying its hold on power, while brazenly turning cyclone relief efforts into a propaganda campaign. In some cases, generals' names were scribbled onto boxes of foreign aid before being distributed. The referendum seeks public approval of a new constitution, which the junta says will be followed in 2010 by a general election. Both votes are elements of what the junta calls its "roadmap to democracy." But the proposed constitution guarantees 25 percent of parliamentary seats to the military and allows the president to hand over all power to the military in a state of emergency - elements critics say defy the junta's professed commitment to democracy. The military refused to honor the results of the 1990 general election won by detained Nobel Peace Prize laureate Aung San Suu Kyi's National League for Democracy party. The referendum was postponed in the worst affected parts of Yangon and the Irrawaddy delta, but people in many peripheral areas that were also affected were asked to vote. "For many of these people this referendum is bizarre, it is illogical. They are surviving by a very thin thread. Why do they have to worry about politics?" said Stothard of ALTSEAN-Burma. In cyclone-hit areas, long lines formed in front of government centers where rations of rice and oil were being distributed. Elsewhere, people clustered on roadsides hoping for handouts. "Help us!" was written in chalk on the side of one home. "Please, don't wait too long," said Ma Thein Htwe, 49, who waited with dozens of other women and children at a monastery in Kungyangon for her ration of rice. Ko Zaw Min, 27, said not enough aid was reaching his community. Each family was given only about a pound (half a kilogram) a day. "I want to build my home where it used to stand, in the field over there," said the farmer, who lost his 9-year-old son and a month-old baby in the disaster. "But I have nothing."