John Key says he will support deputy Prime Minister and Minister of Finance Bill English to be New Zealand's new leader after announcing he is stepping down from the position.
"I have witnessed first hand his leadership style, his capacity for work, his grasp of the economy, his commitment to change and most of all, his decency as a husband, a father, a friend, a colleague and as a politician," Mr Key said.
Mr Key said that under Mr English's leadership National would win next year's election.
"Bill has, I believe, grown a great deal since he was last a party leader. Fifteen years on he is more experienced in the party and political cycles."
Mr English led National to defeat in the 2002 election.
Mr English said Mr Key will leave behind a united team with plenty of talent to take New Zealand forward and build on his legacy.
"Through good times and bad, his strong leadership has been steadfast and this is a more confident, successful and self-assured country because of his contribution. He has truly made a difference."