Captain Matthews, captured at Singapore in February, 1942, ran a resistance movement from inside the Sandakan prisoner of war camp from August 1942 until July 1943 when he was betrayed, arrested and tortured.

The then Lieutenant Russ Ewin, the last survivor of the resistance and a witness to the execution on March 2, 1944, was in Canberra for the presentation of Captain Matthews' medal set to the Australian War Memorial on Monday.

The 98-year-old recalled his former leader with affection and pride.

"Lionel was a great man, dominant to look at and dominant in his leadership," he said.

"I was in a group who would go out to fell timber for the boilers. I took information out [for the underground] and brought back medical supplies and parts for the wireless.

"Lionel had other helpers, but they were very few. None of us knew what the others were doing."

When Captain Matthews was betrayed Mr Ewin and the others lived in constant fear they would be next.

Their leader refused to break and went to his death without giving anybody away.

"He [Matthews] refused to make admissions under brutal torture, beatings and starvation to implicate or endanger the lives of his associates," the citation for his posthumous George Cross states.

A George Cross awarded under these circumstances is the equivalent of a Victoria Cross.

Only seven were awarded to servicemen during WWII and, as of Monday, all are now in the Hall of Valour an AWM spokesman said.

"[Matthews's execution] distresses me every time I think of it," Mr Ewin said.

"I have a memory block; I can't remember any of the burial ceremony after seeing his coffin."

He said the Japanese had treated the remains with respect.

"The camp commandant, Colonel Tatsuji Suga, had fought with the Allies for Japan in WWI. He was a well-educated man," Mr Ewin said.

"Suga said [after the execution] Lionel was the bravest man he had seen.

"Colonel Suga committed suicide, hari kiri, after he was captured by the Allies. He had his orderly help him cut his own throat. I think he was a good man caught up in the military regime and the instructions from above."

David Matthews, who presented the medal set to AWM director, Dr Brendan Nelson, said the war had robbed him of the chance to know his father.

"I was only two-and-a-half when he went away," he said.

"I can recall three or four instances when he was in the room with me."

Mr Ewin joined the taxation department after the war, retiring as the assistant deputy commissioner in NSW in 1976.