Rugby World Cup 2015: Richie McCaw may accept knighthood when he retires says John Key

The Prime Minister says Richie McCaw will probably accept a knighthood when he decides to retire from his rugby career but he doesn't want to "embarrass" him by bringing it up.

John Key told TV3's Paul Henry show this morning that he had yet to ask the All Blacks captain when he would retire.

"I don't want to put him in a position where he feels he has to say something to be. I don't want to put the guy on the spot," he said.

"He will know when the right time is. He loves playing and loves what he is doing. I wouldn't want to embarrass him. He should make that decision himself."

Mr Key said McCaw had made his position "pretty clear" about being honoured.

"If he finally decides to retire he'll probably take it and if he doesn't he'll wait until he does. I don't think he is philosophically opposed," he said.

The Prime Minister said he offered McCaw a knighthood after the 2011 World Cup as the public were pressuring him to do so. He turned it down.

Mr Key said some sportspeople accepted honours at levels below a knighthood in the middle of their career.

Coach Steve Hansen, for one, was made a Companion of the New Zealand Order of Merit - second in rank to a knighthood - for his role as assistant coach at the 2011 world cup. Then coach Sir Graham Henry accepted a knighthood.

Mr Key said: "A knighthood is generally at the end of career or they are truly remarkable in terms of what they've done. Often it's more than just that they are good at their particular position."

When asked if Dan Carter would be offered an honour, Mr Key said he was a great first-five and it was a shame he was leaving the country.