State Services Commissioner Iain Rennie says he hadn't expected the Prime Minister to ring an old family friend directly about the top spy job.
John Key has conceded that he phoned Ian Fletcher about the position at the Government Communications Security Bureau (GCSB), but said on Wednesday that proper process had been followed in the appointment in 2011.
Opposition parties have accused the Government of cronyism over the matter. On Thursday, the Labour Party called on the Auditor-General's Office to investigate the process used to appoint Ian Fletcher due to Mr Key's involvement and the fact he personally knew him.
Applications for the job at the GCSB opened in May 2011. The Prime Minister said on Wednesday that a shortlist of four candidates was rejected by the State Services Commissioner and it was at that point he rang Ian Fletcher and one other person to see whether they were interested in applying.
At a news conference on Thursday afternoon, Iain Rennie said he was surprised when he learned that Mr Key had called Mr Fletcher directly.
Mr Rennie said the two men had discussed other potential candidates, including Mr Fletcher, and agreed to think about it.
Mr Rennie said he had expected that the commission would ring Mr Fletcher to see whether he was interested in applying for the job, but instead he got a call from the then head of the Department of Prime Minister and Cabinet, Maarten Wevers, informing him that John Key had made the call.
Despite that, Mr Rennie said the recruitment process was absolutely above board. However, he said he regrets that it was Mr Key that rang Mr Fletcher, not himself.
"The only issue with perception and with the benefit of hindsight would have avoided, I think, some of the perceptions that we have currently, is if I had contacted Mr Fletcher rather than the Prime Minister."
Mr Rennie said there was no pressure on him to recommend Ian Fletcher for the position.
Later, Iain Rennie told Radio New Zealand's Checkpoint programme it is not unusual for one person to be interviewed for a top public job, saying a sole candidate is considered in about 10% of state sector appointments.
Mr Rennie defended the appointment and the Prime Minister's role and said he would have considered Ian Fletcher for job, even if the Prime Minister didn't suggest it.
"He was someone well-known to me professionally. He was someone who I have a lot of respect for. I had been looking at him for some years and had actually been thinking about potential opportunities for him to return to New Zealand and take up a leadership role in the state sector."
Former spy boss questions process
A former head of the Government Communications Security Bureau says it is unfathomable that only one person was interviewed for the job.
Sir Bruce Ferguson was director of the spy agency for four years until 2010.
He told Checkpoint the sticking point is that the State Services Commissioner and the Prime Minister were happy to appoint the head of the GCSB after interviewing just one person.
"I'm not questioning Ian Fletcher's credentials in this - I don't know him well enough. I accept what every one says. All I'm doing is questioning is the process itself - how one person just comes through at the end, not having gone through a weeding out process, so to speak, beforehand.
Sir Bruce said he knows of three people who were considered for the job, and he believes they should have been interviewed.
Meanwhile, the director of Victoria University's Institute for Governance and Policy Studies said the Prime Ministrer's action opened the recruitment process to accusations of political interference.
Professor Jonathan Boston said it creates problems if ministers start ringing potential candidates and Mr Rennie should have stopped John Key from phoning Ian Fletcher.