A prominent Liberal MP and his spouse have reached a settlement with one of Australia’s leading newspapers following reports questioning the legality of their early relationship.

Sam Groth, a former tennis professional who now serves as the deputy leader of the Victorian Liberal Party, initiated legal proceedings against the Herald Sun. The legal action was in response to articles published in late July that scrutinized the timeline of his relationship with his wife, Brittany.

After engaging in mediation, the involved parties have agreed to conclude the litigation, which was on course for a trial in May, amid escalating legal costs.

It has been disclosed to AAP that the settlement, which remains confidential, includes a public apology as well as compensation amounting to several hundred thousand dollars.

The controversy began with a front-page article by journalist Stephen Drill, which suggested Groth and his wife began their relationship while he was coaching at Templestowe Park Tennis Club in 2011.

The article implied a potential legal issue for Groth, as Victorian law could have classified him as a sex offender due to their ages at the time—Groth being 23 or 24, and Brittany 16 or 17.

The articles have disappeared online and related social media posts are also expected to be pulled down.

The Groths alleged the articles were defamatory and breached Ms Groth’s privacy under federal privacy laws that came into effect in June and allow damage claims up to $478,000.

The legal claim was poised to become a test case to an exemption for professional journalists and media publishers when collecting information for preparation to publish or publication of material that has the “character of news, current affairs or documentary”.

In Federal Court in October, the Groths’ barrister Sue Chrysanthou SC argued the stories were not news but “salacious gossip”.

“News is factual information, it is not fiction,” she said.

The outlet’s barrister Matt Collins KC argued the clause was a blanket exemption for journalists regardless of the content published.

Chrysanthou said the Herald Sun was planning to make a public interest defence to the defamation allegation and there was no defence of truth.

Justice Shaun McElwaine warned the ultimate loser of the case was likely to face significant cost burdens.

The Groths and News Corp Australia have been contacted for comment.