He made the decision days after celebrating eight years as Prime MInister and a decade as leader of the National Party.

A special caucus meeting will be held on December 12 to choose a new leader.

During a surprise press conference today, Key outlined his highlights including the overhaul of justice agencies, trade liberalisation and advanced race relations.

Key said the job had meant an extraordinary level of sacrifice, intrusion and pressure for his family as well as opportunities.

He told reporters that 10 years had been long enough in the top job, and he was happy to leave on his own terms.

“I feel that leaders tend to stay too long… I felt this was the opportunity for me to go out on top,” he said.

Key said he would vote for deputy leader Bill English if he was put forward in the caucus vote.

He said he believed English could lead the party to victory at the 2017 election.

more to come

– AAP