The British government says there's been some progress in bringing aid to victims of the cyclone in Burma, but not nearly enough.

Aid groups warn the official toll of 62,000 dead or missing could rise unless the neediest survivors get help immediately.

Britain's International Development Secretary, Douglas Alexander, says Burma's military government is now giving more latitude to some aid agencies to deliver relief supplies.

Meanwhile, a boat carrying aid to the victims of Cyclone Nargis in Burma has sunk while trying to reach people in the south of the country.

The International Federation of Red Cross and Red Crescent Societies says the double-decker boat hit a submerged tree trunk and started taking on water.

A federation spokesman in Burma, Joe Lowry, says most of the supplies, enough for about 1,000 people, were lost.

He says they included fresh water, purification tablets, rice, clothes and surgical masks.

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