Clive Palmer: on the Victorian hustings later this morning.

Clive Palmer and wife Anna have spoken out about their relationship. Photo: Bloomberg

Billionaire businessman Clive Palmer played father of the bride to his now-wife at her first wedding, the couple have revealed.

Mr Palmer and his wife Anna have told their story to the ABC's Australian Story, telling of a friendship that began after both lost their partners to cancer within weeks of each other.

Mrs Palmer arrived in Australia in 1993, aged 18, to marry her first husband Andrew Topalov.

Her parents were in Bulgaria and unable to attend the wedding, so Andrew turned to his trusted friend Mr Palmer and his then-wife Sue to stand in as the bride's parents on her big day.

"He made a lovely speech, which he's very capable of," Mrs Palmer said.

Andrew Topalov and Sue Palmer both died of cancer in 2006.

Mr Palmer says one of his greatest challenges at the time was raising his daughter Emily, who was approaching adolescence.

He reached out to Anna, knowing she too was grieving.

"I never thought of Anna as a partner in life at that stage but after about two years we started going out together and then finally we got married," Mr Palmer said.

Mrs Palmer says she saw her husband's business interests as "irrelevant" when they were starting out.

"I just thought he was trying to impress me and exaggerating everything he said," she said.

They now have a four-year-old daughter together, Mary.

Mr Palmer, 58, is 20 years older than Anna.

"I mean I was very grateful that anyone would want to spend any time at all with me you know?" he says of his wife.

"Let alone, let alone as someone as attractive and as vital as she was and she is."

Australian Story airs on Monday, May 7 at 8pm (AEST) on ABC1.

AAP