Prime Minister John Key and Foreign Minister Murray McCully will start campaigning in force for former rival Helen Clark this week, travelling overseas to push her case for the United Nations Secretary-General role.
Mr Key will travel to China with a trade delegation tomorrow and says he will raise Helen Clark's candidacy in his formal meeting with President Xi Jinping and Premier Li Keqiang.
"I will be reaffirming not only her credentials but her strong commitment to China and the role that she played in the signing of the China FTA [free-trade agreement]."
As one of the five permanent members of the Security Council, China has a critical role in the process of appointing the Secretary-General.
Mr McCully leaves this weekend for the UN in New York and will then visit Britain, Germany and France. He said he would use the opportunity to support Helen Clark's candidacy in his meetings with foreign ministers.