The head of the US Senate Finance Committee is in New Zealand for three days of talks.
Senator Max Baucus of Montana (Democrat) is expected to discuss progress on negotiations for a Trans-Pacific Partnership.
If agreed to, the TPP would free-up trade between Australia, Brunei, Chile, Malaysia, New Zealand, Peru, Singapore, the United States and Vietnam. Mexico and Canada are also scheduled to join.
New Zealand Trade Minister Tim Groser welcomed the arrival of Senator Baucus, who is seen as a big influence in trade policy, especially free trade agreements. He is Washington's fifth longest-serving senator.
Senator Baucus will also meet Prime Minister John Key, Speaker Lockwood Smith, industry leaders and Maori.