Myanmar, formerly known as Burma, requires foreign aid money to be converted first into foreign exchange certificates at a fixed price and then into the country's national currency, the kyat.
These certificates have been valued at as much as 25 per cent less than the market value of an equivalent number of US dollars.
Jody Williams, Nobel Peace Laureate and co-founder of the Nobel Women's Initiative, told Al Jazeera that the complicated currency exchange system shows that Myanmar's military government is still hampering aid efforts.
"It's a very clear example of why we are concerned. We were able to meet Myanmarese along the Thai-Myanmar border and their stories of aid not reaching them are really alarming, to put it mildly.
"I hope this will inspire governments to have aid go directly to agencies which work directly with people and not to the junta, who steal the money and the aid," she said.
"They don't have a very impressive record over the years," she added.
Despite currency losses, John Holmes, the UN's humanitarian affairs chief, said he was encouraged by signs of recovery, such as house repairs and field ploughing in the disaster zone.
He did, however, underline the urgent need for more aid, and said survivors will be dependent on aid for at least another six months.
Holmes visited the Irrawaddy Delta area this week and said he had told General Thein Sein, Myanmar's prime minister, that greater collaboration was essential to help rebuild.
"We were discussing how much progress we have made in the last two months. What I was arguing was that we needed to go on with this kind of spirit of working together ... on the humanitarian side, in a non-political way."
Earlier this month, the UN raised its appeal for the first year of relief operations to $481m , up from $201m.
An assessment released this week by the UN and the Association of Southeast Asian Nations (Asean) estimates that the combined cost of rebuilding houses, schools, and other infrastructure, as well as providing food aid and other essential services, is about $1bn over three years.
The assessment comes a week after the UN said it was ending aid flights to Myanmar at the beginning of August.
The UN said it was a routine step as the country shifts to rebuilding homes, buildings and schools destroyed by Nargis.
The May cyclone devastated much of the region south of Yangon, killing 85,000 people and leaving 50,000 missing.
|The UN-Asean report said more than 4,000 schools were damaged or destroyed [EPA]
Unicef, the UN's children fund, said on Friday that about 700,000 children were in need of long-term aid in Myanmar due to the devastating effects of Nargis.
Ramesh Shrestha, Unicef's Myanmar representative, said: "While we have observed a gradual improvement in the situation for children, and have avoided the emergence of major epidemics, we must maintain our efforts."
Unicef's appeal after the cyclone was for $90m for aid operations up to April 2009. To date, it has raised less than half of that sum.
In the crucial days after the cyclone hit, Myanmar authorities blocked access for foreign relief workers, raising fears that thousands more people would die.
The authorities eased their stance after a visit and pledge by Ban Ki-moon, the UN secretary-general, but aid groups have said access to the worst-hit southern delta is frequently prohibited.
In May, Burmese authorities said the number of dead and missing from the cyclone was about 140,000 people.
Major findings from the UN-Asean report revealed the about 700,000 homes, 75 per cent of health facilities, and more than 4,000 schools were damaged or destroyed.
Nargis flooded more than 600,000 hectares of agricultural land, killing up to 50 per cent of livestock in the affected areas, and destroying fishing boats, food stocks and agricultural implements.
According to the UN-Asean report, damages and losses amount to $4bn.