United Nations Secretary-General Kofi Annan has toured tsunami-hit areas of Sri Lanka still struggling to recover from the devastating Indian Ocean tsunami. Mr. Annan viewed the southern coast by helicopter, and he visited the eastern town of Hambantota with Sri Lanka's prime minister and the president of the World Bank. The World Bank chief later said the bank could hand out up to one-point-five billion dollars in tsunami aid. Officials who viewed coastal areas in recent days have expressed awe at the scale of destruction and have said there is an urgent need to help survivors. Public and private pledges to the tsunami relief effort now top five billion dollars, and the world's leading industrial nations have agreed to suspend the affected countries' debt repayments -- saving south Asian nations additional billions. Casualties from the earthquake and tsunami continue to increase, with most of the more than 153,000 confirmed deaths on the northern Indonesian island of Sumatra. Health officials worry that disease and untreated injuries among survivors could push the toll even higher.