Vikki Campion's ex-fiance reveals their wedding was cancelled three months before the date.

Last week, news broke the Australian Deputy Prime Minister Barnaby Joyce is expecting his fifth child with his new partner, former staffer Vikki Campion.

The 50-year-old politician announced his separation from his wife of 24 years, Natalie Joyce, in December last year. They have four children together.

And, as the front page of the Daily Telegraph showed Campion heavily pregnant with Joyce’s child, due in April, many lives were apparently shattered.

Speaking for the first time since the news broke, journalist-come-digital-consultant John Bergin told News Corp he and Campion were due to be married on November 5, 2016, but separated three months before their wedding date.

“I’m just a spectator in this, like everyone else,” he said. “We split in August 2016 and we haven’t spoken to each other since.”

After the 2016 election and Joyce's appointment to the role of Deputy Prime Minister, the minister cleaned out the former media squad but kept Campion in employment and took her to Canberra, News Corp reports.

Campion, 33, remained in his employment until July 2017 when she was hired by Joyce's friend, Nationals Senator Matthew Canavan and then by the party's whip Damian Drum. On Monday, Drum told ABC he was aware of 'rumours' of an affair between the two but had been told it had ended, The Guardian reports.

When asked by News Corp if his split with Campion had anything to do with her starting a relationship with Joyce, Bergin said he "would rather not comment on such matters".

Listen: Radio host Kate Langbroek said sleeping with a married man is a rotten thing to do. Post continues below. 

As speculation around the affair continues, Bergin is left fielding questions and reliving a difficult, emotional time – but this time in the public eye.

"It seems that some people feel they can just make things up," he said, in reference to a rumour circulating social media that Campion refused to return the engagement ring Bergin had given her.

Meanwhile, the Deputy PM is facing questions over how his girlfriend came to take a job with Canavan, and over the timing of the affair after Natalie Joyce said she is sure it "started when [Campion] was a paid employee".

According to AAP, the statement of ministerial standards stipulates family and partner cannot be employed by any members of government "without the prime minister's express approval."