The International Federation of the Red Cross (IFRC) said its first aid shipment to cyclone-hit Myanmar sank Sunday after hitting a submerged tree while travelling by river.

The crew and four Myanmar Red Cross workers managed to reach safety but relief supplies intended to help around 1,000 people were lost, Geneva-based IFRC said in a statement.

Efforts were under way to salvage some of the supplies that included water flown in on the first IFRC flight to arrive Friday.

'This is a great loss for the Myanmar Red Cross and for the people who need aid so urgently,' said spokesman Aung Kyaw Htut. 'This would have been our very first river shipment and it will delay aid for a further day.'

The boat was travelling from Yangon to Mawlamyinegyun, some 12 hours by boat when it sank near Myinka Gone village.

It was carrying 100 bags of rice, 5,000 litres of drinking water, 10,000 water purification tablets, 200 jerry cans to carry water, as well as household kits and sanitary items.

The International Federation's disaster manager in Yangon, Michael Annear, described the sinking as 'a big blow. Apart from the delay in getting aid to people we may now have to re-evaluate how we transport that aid.'