Former marketing manager and personal trainer Brendan Farnhill was hired for a three-month role in the newly-established office in December, Mr Farnhill's LinkedIn profile showed.

Mr Farnhill's partner, Jeff House, was instrumental in setting up the office headed by former Liberal MLA Brendan Smyth.

Mr Smyth's job was created and his appointment made by Chief Minister Andrew Barr. Mr House was the public servant charged with the detail of the appointment, including working out what to call the job and how much to pay.

But Mr Smyth stressed Mr Farnhill got the job because he was the most suitable applicant for the job.

"The job was advertised, I formed a selection committee of three members, of which I was one, the three members looked at the applications we had received and decided I would then talk to a number of applicants. I had discussions with a number of applicants and the person who won the job was the most suitable applicant," Mr Smyth said.

"I'm not going to discuss personnel details, I simply had six applicants for a job, they were shortlisted, they were interviewed and the most suitable candidate was chosen and that was the decision of the committee. The process that was required was followed and it was followed to the tee."

Similarly, Mr House said given the appointment was made using strict public service processes and he was not a party to the selection, there was no conflict of interest.

He said Mr Smyth was appointed by the Chief Minister following a "very public call" for expressions of interest, and that another staff member in the Office of International Engagement also had a partner who worked in the same directorate.

"No one is prohibited from applying for jobs within the ACT Public Service because of who else may already be employed within the service. Nor should they be because it would be discriminatory, in every sense of the word, to do so. We want the best people working for us and if they're qualified and win jobs fair and square then they should not be denied the opportunity to do the job," Mr House said.

Mr Smyth's own appointment as the city's first Commissioner for International Engagement three months before last year's ACT Election raised eyebrows.

Emails released under Freedom of Information laws showed Mr House, who is deputy director-general of the Chief Minister's directorate, first floated the position on July 4 with executive director of Innovate Canberra Ian Cox.

Subsequent emails showed Mr House was instrumental in shaping the role, including writing a document that would outline the commissioner's key duties.

While there was no record of an approach to Mr Smyth nor an application, Mr Smyth said Mr House had called him about the job.

In November, Auditor-General Maxine Cooper said the appointment lacked transparency and highlighted the speed with which it was announced (Mr Smyth was confirmed as the commissioner on July 15, 11 days after Mr House first emailed Mr Cox about creating the position).

While Dr Cooper cast no aspersions on Mr Smyth's qualifications for the role, she found little explanation of how Mr Smyth's salary, of $252,000 plus benefits, was chosen, other than an email from Mr House on July 4, saying, "My current thinking is to peg this position to the public servant equivalent of a ministerial salary," but giving no reasons.

Since assuming the role, Mr Smyth has travelled to Wellington three times and Singapore once to promote Canberra, with plans to strike up relationships with Japan, China and the US this year.

"Building reputation and prestige and relationships always takes time and this isn't a sprint, it's a long term commitment to furthering Canberra presence in the world," Mr Smyth said.