Prime Minister Lee Hsien Loong has written to his Australian counterpart, Mr Scott Morrison, to convey deepest condolences over the death of former prime minister Bob Hawke on behalf of the Government and people of Singapore.

In a letter, PM Lee said that Mr Hawke's strong leadership as prime minister from 1983 to 1991 ushered in a period of prosperity for Australia.

Mr Hawke died at the age of 89 on Thursday.

"He will be remembered for his determined efforts to bring together the unions, businesses and government to reform Australia's economy, and for his bold vision of providing greater access to education and healthcare for all Australians," wrote PM Lee.

He said Mr Hawke was a good friend of Singapore who established a close rapport with Singapore's leaders as bilateral ties blossomed.

He noted the Australian statesman visited Singapore in 1984, 1987 and 1989 as he advocated closer ties between Australia and Singapore, as well as the whole of Asia.

"Mr Hawke's critical role in bringing the Asia-Pacific Economic Cooperation (Apec) group into being will long be remembered, especially at a time when the global consensus on free trade is facing headwinds," PM Lee wrote.

He recalled attending the first Apec meeting in Canberra when he was the Minister for Trade and Industry in 1989. "Years later, I was happy to welcome Mr Hawke to Singapore when we hosted the Apec meeting in 2009," he said.

"Mr Hawke was a major figure in international affairs, and will be missed by many. Ho Ching's and my thoughts are with Mr Hawke's family, and the people of Australia during this time of loss," PM Lee wrote, referring to his wife.