Jun 4, 2008 (AFP)‚ Four US Navy ships which had been stationed off cyclone-hit Burma with relief supplies and aircraft will return to normal duties after the junta rejected their help, US officials said Wednesday.

The USS Essex group has been idling off the coast of the country once known as Burma since 13 May, but the regime — notoriously mistrustful of the West — repeatedly refused any relief supplies from foreign militaries.

"Over the past three weeks we have made at least 15 attempts to convince the Burmese government to allow our ships, helicopters and landing craft to provide additional disaster relief for the people of Burma," Admiral Timothy Keating, commander of US Pacific Command, said in a statement.

"But they have refused us each and every time. It is time for the USS Essex group to move on to its next mission."

Several aircraft with heavy-lifting capabilities will be left in Thailand in case they are needed by aid agencies to help with the relief effort, he added in the statement issued by the US embassy in Bangkok.

The ships were carrying aid supplies including 15,000 water containers and purifying kits, as well as 14 helicopters and 1000 Marines.

The four Navy vessels will leave on Thursday, but Keating said they could return if the Burmese junta had a change of heart.

"I am both saddened and frustrated to know that we have been in a position to help ease the suffering of hundreds of thousands of people and help mitigate further loss of life, but have been unable to do so because of the unrelenting position of the Burma military junta," Keating said.

Burma’s ruling generals angered the international community by severely restricting foreign relief supplies after Cyclone Nargis hit one month ago, leaving 133,000 people dead or missing and 2.4 million people in need of food, shelter and medicine.

After a UN-led diplomatic effort, the junta agreed on 23 May to allow foreign aid workers access to the delta, but progress has been slow, with a lack of transportation and lifting equipment further hampering operations.

Last week, French navy ship the Mistral handed over its payload of aid to the United Nations in Thailand after the junta refused to let the vessel into the country.