The number of people dead after one of the world's strongest typhoons struck the Philippines has risen above 6,000, the government said Friday, with nearly 2,000 others still missing.

Five weeks after Super Typhoon Haiyan destroyed entire towns across the nation's central islands, the National Disaster Risk Reduction and Management Council put the official death toll at 6,009, making it the Philippines' deadliest recorded typhoon.

The council said it is still looking for 1,779 missing people amid an international relief and rehabilitation effort covering a large devastated area about the size of Portugal.

The number of people confirmed dead or unaccounted for continues to rise steadily. On November 23, more than two weeks after the storm struck, officials put the death toll at 5,235 and listed 1,613 people as still missing.

The latest official count puts Haiyan nearly on par with a 1976 tsunami in the southern Philippines, generated by a major undersea earthquake in the Moro Gulf, that left between 5,000 and 8,000 people dead.

The Haiyan toll has already surpassed Tropical Storm Thelma, which unleashed floods that killed more than 5,100 people in the central city of Ormoc in 1991, previously the country's deadliest storm.

The United Nations asked donors this week to more than double their emergency aid donations to the Philippines to $791 million to cover needs over 12 months.

The government said more than four million people lost their homes to either Haiyan's 315 kilometres (195 miles) per hour winds or tsunami-like storm surges, and some would continue to need food aid as well as shelters and jobs.

As part of the international aid effort, an Indonesian official involved in the rebuilding of Aceh after the devastating 2004 Indian Ocean tsunami was in the Philippines on Friday to help the neighbouring country recover from the typhoon.

Senior government official Kuntoro Mangkusubroto visited the hard-hit central city of Tacloban at the Philippine government's invitation to provide insights on managing large-scale recovery programmes, the United Nations Development Programme said in a statement.

"I'm here to offer the government and the international community my experience as the coordinator of rehabilitation of Aceh," Mangkusubroto said in the statement.

"I look forward to sharing my expertise and contributing to designing an efficient recovery plan for the areas devastated by Typhoon Haiyan," he added.

"The aim of this significant visit by Dr. Kuntoro Mangkusubroto is to share ways to ensure that the recovery process in the Philippines will build resilience against future typhoons," said the UN's humanitarian and resident coordinator Luiza Carvalho.

Mangkusubroto was the director of Indonesia's National Agency for Reconstruction and Rehabilitation for Aceh and Nias islands, which accounted for about half the 200,000-plus deaths caused by the 2004 tsunami.