Red Cross officials have accused the authorities in India's tsunami-struck Andaman and Nicobar Islands of "hijacking" aid supplies.
The Indian military has played a key role in getting aid to the islands
A spokesman for the agency said relief materials seized on the islands had been found with government workers.
Island officials have not commented on the charge but stress their policy that foreign aid to the islands only be distributed through the government.
Aid has yet to reach remote parts of many islands, a BBC correspondent says.
More than 1,800 people are now known to have died on the Andaman and Nicobar Islands after sea surges triggered by a massive underwater earthquake struck there on 26 December.
At least a further 5,600 people are still missing after the disaster, the Andaman and Nicobar administrative chief, Ram Kapse, said.
The official death toll in India, including the islands and mainland parts of Tamil Nadu state, now stands at 10,672.
Relief material 'robbed'
An official from the Indian Red Cross Society, Basudev Dass, told the BBC that they had been informed by the Andamans authorities that all non-governmental agencies - Indian as well as international - would be barred from working on the islands.
Until now only the United Nations children's agency, Unicef, had been given permission to operate outside of the capital, Port Blair.
Mr Dass said the local administration told him it was capable of conducting the relief operation without any need of external help.
The BBC's Subir Bhaumik says there have been continued complaints of shortage of relief material from remote areas as well as reports of hungry people looting supply trucks in at least four areas.
Mr Dass said Red Cross supplies shipped to the islands' capital, Port Blair, were seized at the docks on Thursday, apparently for distribution by the government.
"They hijacked our relief material. They robbed it," Mr Dass told the Associated Press news agency.
"They want to take all the relief material and distribute it. We are very clear that we will go and distribute it to the real beneficiaries," he said.
The Indian branch of Rotary International says its offer to build 1,500 homes for displaced islanders had been rebuffed.
Mr Kapse said the government would welcome the offer of building materials from aid agencies but would undertake the construction work itself.
The Indian government and military has been managing the aid operation for the Andaman and Nicobar Islands.
Visitors are banned from visiting much of the Andamans.
Correspondents say the islands are of high military importance to the government. In addition, the government has sought to restrict outside access to a number of primitive tribes on the islands.