The United Nations head of humanitarian aid says he is worried about announced restrictions on relief efforts in Indonesia's Aceh province.

Indonesian officials recently announced mandatory registrations for aid workers and military escorts for relief groups venturing outside the hard-hit cities of Banda Aceh and Meulaboh. The government said the escorts are needed to protect workers from Aceh rebels.

Authorities also said they want foreign troops to leave the country by late March or sooner.

U.N. aid chief Jan Egeland says the most important thing now is to save lives and not impose deadlines.

A senior official with the U.S. Agency for International Development (William Garvelink) tells VOA that USAID workers in Aceh have not yet observed any changes in procedures since the government announced the new measures.

Relief efforts continue throughout southern Asia as survivors left homeless by the tsunami disaster are now especially vulnerable to diseases such as malaria and cholera.

The Asian Development Bank estimates some two million people could fall into poverty as a result of the tsunami. The death toll from the disaster now stands at nearly 160,000 people.