"I went to school with his brother. His brother was way brighter than Grant Robertson."
Mr Key said he couldn't recall particular occasions when he'd met with Mr Fletcher subsequent to their schooldays.
"I'm sure I may well have done so. What I can say, if the member wants to know, is my mother was best friends with Ian Fletcher's mother. If that makes a conspiracy, fair enough."
Mr Key later told reporters he knew Mr Fletcher only "vaguely" before his appointment to the GCSB job. He said he advised Mr Rennie of his relationship with Mr Fletcher at the time and told him Mr Fletcher was a good appointment.
"He was very bright, he used to work for Tony Blair and various other Governments. He was one of the most senior civil servants in the British system. He's a very good person, he's doing a great job."
Asked if Mr Fletcher was a friend he said: "I wouldn't go that far. I haven't seen the guy in a long time."
But Mr Browning said he had been told by a friend who also knew Mr Fletcher that he and Mr Key continued to stay in touch after their school days. "He [Mr Fletcher] would say to my acquaintance that anytime he was in New Zealand he would always have a meal with John Key."
Mr Browning understood Mr Key, Mr Fletcher and his brother "were all mates" from their time at Burnside High School in Christchurch.
While the relationship between Mr Key's family and the Fletchers was healthy, "I don't think it's healthy for him [Mr Fletcher] to be in that position.'
"He's far too familiar for somebody in that role. We just do not expect to have a situation in New Zealand that someone that can spy on any of us is the Prime Minister's mate. It's just totally inappropriate. He should not have hired him, he should have hired someone else."
The GCSB is not permitted to spy on New Zealand citizens or permanent residents but broke the law when it spied on permanent New Zealand resident Kim Dotcom ahead of the police raid on Mr Dotcom's Helensville mansion in early 2012.
Mr Robertson said Mr Fletcher was present at the February 16 meeting last year "where questions were raised about the legality of the agency's surveillance of Kim Dotcom"
"Yet John Key claims he was never told about the concerns until September despite receiving a number of briefings from Ian Fletcher on intelligence matters before then.
He said it was vital New Zealanders were reassured there were no private conversations between Mr Key and Mr Fletcher "about this issue given John Key's revelation today that their families have a close personal connection".
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