WASHINGTON (CNN) -- After concerns that Myanmar authorities improperly took some previous relief supplies, Myanmar is now allowing U.S. government aid workers to give aid directly to private aid groups.
U.S. relief supplies are unloaded at Yangon Airport on Friday.
State Department spokesman Sean McCormack said Friday there have been questions about whether supplies have reached victims of the cyclone that ravaged the southern part of the nation two weeks ago.
"We are doing our best to make sure that what is delivered in Yangon makes it down to the affected areas to those who need it," he said at his midday briefing in Washington.
"Given the current circumstances, you can't construct a perfect system for doing that."
"We have four C-130 relief flights that landed in Yangon today. Two of the shipments were handed over directly to NGOs," he said, using the shorthand for non-governmental organizations, or private relief groups. "That is the first time that has happened."
"The aid will be distributed via the Emerson Trust, I think it's about 100,000 tons; and about 400,000 via the World Food Programme. And representatives from Emerson and World Food Programme will be able to travel to affected areas," he said.
Myanmar's ruling military junta has been reluctant to allow outsiders in to supervise the distribution of aid, although they have loosened their restrictions in the past week to allow more access by NGOs.
"We are planning four to five flights for both Saturday and Sunday and it is our hope that some of those shipments again will be handed over directly to international NGOs for distribution in affected areas," McCormack said. Watch the despair of the Irrawaddy delta »
He also said a representative of the U.S. Embassy in Myanmar will be taken by Myanmar government officials on a tour of the areas damaged in the cyclone, though he would not predict how widely or freely the diplomat would be able to travel.
The United States continues to push for greater access to Myanmar, both to allow more shipments of aid and to allow the entry of U.S. technical experts.
"The situation is changing. Clearly there is a scope of assistance that is needed that goes well beyond what is currently provided," McCormack said. "We, as well as others, are prepared to provide that assistance. ... So we are going to keep working the politics of this."
So far U.S. aid may have helped some 135,000 people, officials say, a small number compared to estimates that 2.5 million people need assistance.