Key Points:

John Key has two long-lost half-brothers living on the other side of the world.

When the Weekend Herald tracked down one of them in the south of England, Martyn Key said he had only vaguely known that he had a half-brother, and certainly had no idea about his business or political career: "We are still shell-shocked with the news of my half-brother and his brilliant career, which we will follow with great interest."

Martyn and his older brother, Peter, are the children from John's father's first marriage to a Hull woman, Beatrice Barnard, in 1934.

The couple divorced after the war and George Key married Ruth Lazar, with whom he had three children - Liz, Sue and John.

George Key was somewhat of a mystery to all his children. He left Beatrice when the children were young - Martyn remembers him coming home from the war and then suddenly not being there. He left Ruth not long before he died in 1969, when John was aged 7.

The only contact between the two sets of half-siblings was when Liz went to England on her OE about 30 years ago. She met Martyn several times.

"He looked exactly like Dad. I met him at a train station in London and he was absolutely identical," says Liz.

Beyond those visits, Martyn had not heard of his half-sisters or famous half-brother.

Martyn, now aged 68 and living in Southsea, Hampshire, retired more than 20 years ago after selling up his business, a chain of chemist shops. His older brother, Peter, 74, has lived in Canada for many years where he was a logger. Their mother, Beatrice, died in 1976, aged 61.

Martyn says what he knew of his father was what his mother had told him. "He fought in the Spanish Civil War, came back and then was in the Royal Artillery.

"His World War II experience included a spell in Mombasa - also an attachment to the Intelligence Corps as he could speak Russian. The Keys were blessed with brains and were well-read."

Upon his return from the war, George got into the family business, surgical appliances.

Liz, who was 19 when her father died, remembers him as stubborn and a voracious reader.

Martyn remembers his grandparents well, especially George's mother, Millie. "She was very interested in antique furniture and ... went to most big sales including the one held at the German Embassy in London just after the war and bought Goering's bedroom suite, which was huge," he says.