Aid organisations in Indonesia's tsunami-devastated province of Aceh are experiencing frustration at not being able to move supplies fast enough. The influx of aid is causing a bottleneck.

While several aircraft a day drop off pallets at Banda Aceh airport, many pallets sit idle for up to two days without being moved.

Aid organisations are having difficulty securing transport to shift the much needed relief to outer lying areas, while helicopters are in short supply.

But the United Nations says that relief workers are close to getting at least some food to everyone left hungry by the Indian Ocean tsunami in Sri Lanka, the Maldives and Somalia.

Kevin Kennedy, a senior official in the UN Office for the Coordination of Humanitarian Affairs, says by this weekend the international relief effort will have delivered at least an initial shipment of food and other emergency supplies to "every person in need" in Sri Lanka.

He says in the Maldives, a country made up of more than 1,200 coral islands, some 220 of which are inhabited, enough food is now on hand to aid all 50,000 in need and distribution has begun.

Enough food to satisfy emergency needs is also in place in Somalia. Kennedy says deliveries in Somalia have begun despite the uncertain security situation and other logistic challenges.

But Kennedy says Indonesia's devastated Sumatra and Aceh provinces "remain the heart of the crisis and probably where the biggest challenges are".

Officials believe that hundreds of thousands of people remain stranded in that area following the December 26 tsunami and the powerful earthquake that triggered it.

Kennedy briefed reporters in New York shortly after UN secretary-general Kofi Annan inspected the scarred landscape of Aceh province from a helicopter. Kennedy said relief efforts targeting the two provinces at the north-eastern tip of Indonesia's Sumatra island would now be getting a big boost from a just-opened air bridge from Malaysia.