The two nations were both part of the Trans-Pacific Partnership (TPP) trade negotiations until President Trump withdrew the United States from the TPP in January 2017. The shift to normal relations between the two nations was marked by a U.S. naval ship visit to New Zealand in November 2016. This was the first such visit since 1983. New Zealand is a unicameral, mixed-member-proportional (MMP), parliamentary democracy. While the National Party had the most seats, it was Labour that formed a government in coalition with the populist New Zealand First Party with the support of the Green Party. The National Party Leader and former Prime Minister Bill English became Opposition Leader following Ardern's swearing in as Prime Minister. During the mid-1980s, the United States suspended its alliance commitments to New Zealand due to differences over nuclear policy. These differences over nuclear policy significantly constrained the relationship for many years. The relationship has now largely moved beyond past differences over nuclear policy. The countries have a strong focus on a stable and secure Asia-Pacific region and on a robust international architecture that supports and open trade and investment system, a rules based international legal framework, and sound principles of good governance. New Zealand and the United States also participate in joint humanitarian and disaster relief exercises with Pacific Island states. Several organizations and groups, some involving Members of Congress, help promote bilateral ties between the United States and New Zealand, including the United States-New Zealand Council in Washington, DC, and its counterpart, the New Zealand-United States Council in Wellington; and the bipartisan Friends of New Zealand Congressional Caucus and its New Zealand parliamentary counterpart. The U.S.-N.Z. New Zealand legislation made the country nuclear-free, which had the effect of barring visits from nuclear-powered or nuclear-armed ships. The United States had, and still has, a policy of neither confirming nor denying the presence of nuclear weapons on U.S. Navy ships. New Zealand's commitment of special forces from 2001 to 2009 and regular troops and other assistance, particularly the Provincial Reconstruction Team (PRT) in Bamiyan Province, Afghanistan from 2003 to 2013, demonstrated to many U.S. policymakers New Zealand's value as a political, diplomatic, and military partner. The United States welcomes New Zealand's participation in RIMPAC (Rim of the Pacific Exercise), the world's largest multinational naval exercise. In recent years, New Zealand's independent defense policy has focused on contributing to international peace operations, New Zealand's maritime environment (including its Exclusive Economic Zone [EEZ] and the Southern Ocean), the South Pacific, Antarctica, and cybersecurity. New Zealand armed forces made a significant contribution in support of the allied cause in World War I and World War II. New Zealand has played a key role in promoting peace and stability in the South Pacific in places such as the Solomon Islands, Timor-Leste, and Bougainville in Papua New Guinea. New Zealand also provides development and disaster assistance to the region. New Zealand's Island Relations

New Zealand has a set of relationships with South Pacific islands that is in some ways similar to the relationships between the United States and various island nations in the Western Pacific, such as the Freely Associated States. China is expanding its presence in Antarctica, which, like the South Pacific, is a region where New Zealand has significant interests. In the lead-up to the September 2017 election, New Zealand, along with Japan, played a leading role by remaining committed to a deal with TPP-11 countries to cut trade barriers in the Asia Pacific. Appendix B. Wellington Declaration
Wellington Declaration on a New Strategic Partnership Between New Zealand and the United States 
Media Note
Office of the Spokesman
U.S. Department of State
Washington, DC
November 4, 2010
Minister of Foreign Affairs for New Zealand Murray McCully and Secretary of State Hillary Rodham Clinton of the United States met today to reaffirm the close ties between their two nations and to establish the framework of a new United States-New Zealand strategic partnership to shape future practical cooperation and political dialogue.
New Zealand is a close partner of the United States and welcomes a U.S. presence in the Asia-Pacific region. New Zealand and the United States engage each other across a broad spectrum of policy areas, including Islamist extremism, South Pacific regional issues, intelligence cooperation, and Antarctica. Issues for Congress related to New Zealand include oversight and appropriations related to international security cooperation, counterterrorism (CT) and countering violent extremism (CVE), and intelligence cooperation among the so-called "Five Eyes" nations, which include New Zealand. U.S.- New Zealand ties are bolstered by shared cultural traditions and values as well as common interests. New Zealand is a stable and active democracy that has supported liberalizing trade in the Asia-Pacific region. It is one of the 11 nations in the proposed Trans-Pacific Partership (TPP) trade grouping, from which President Trump withdrew in January 2017. New Zealand also has a history of fighting alongside the United States in major conflicts including World War I, World War II, Korea, and Vietnam. New Zealand is a regular contributor to international peace and stability operations and has contributed troops to fight Islamist militants in Afghanistan, where New Zealand had a Provincial Reconstruction Team (PRT) in Bamiyan Province until 2013, and more recently in Iraq where it is training Iraqi military personnel. New Zealand's foreign policy largely supports a rules-based international order, collective approaches to promote stability, and the peaceful resolution of disputes.
During the mid-1980s, the United States suspended its alliance commitments to New Zealand due to differences over nuclear policy. New Zealand legislation made the country nuclear-free, which had the effect of barring visits from nuclear-powered or nuclear-armed ships. The United States had, and still has, a policy of neither confirming nor denying the presence of nuclear weapons on U.S. Navy ships. These differences over nuclear policy significantly constrained the relationship for many years. In November 2016, a U.S. naval ship visited New Zealand for the first time since 1983. This marked for many observers the return to a normalization of bilateral relations.
The bilateral relationship between the United States and New Zealand was strengthened significantly through the signing of the Wellington Declaration in November 2010. The Wellington Declaration, and a subsequent Washington Declaration (2012), opened the way for increased military exchanges and joint participation in military exercises. With the Wellington Declaration, then-Secretary of State Hillary Clinton and former New Zealand Prime Minister John Key signaled that differences over nuclear policy had been set aside. New Zealand is now a participant in the U.S.-hosted Rim of the Pacific (RIMPAC) naval exercise. RIMPAC, the world's largest maritime military exercise, seeks to promote interoperability among participating militaries. New Zealand favors an open and inclusive strategic and economic architecture in the Asia-Pacific.
New Zealand has shown a commitment to humanitarian assistance and conflict resolution both in the South Pacific and beyond. In the South Pacific region, it provides foreign assistance and disaster relief and is widely credited with promoting regional stability. New Zealand participates in the annual Pacific Partnership maritime operation, which seeks to improve humanitarian assistance and disaster relief preparedness in the region. New Zealand's commitment to promoting regional security is demonstrated by its past role in helping to resolve conflict in places such as Bougainville, Papua New Guinea, Timor Leste, and the Solomon Islands. New Zealand has also contributed to peace operations in places such as Bosnia, Sierra Leone, and Kosovo outside its region.
The National Party and the Labour Party have traditionally been the two leading political parties in New Zealand. New Zealand has a Mixed-Member-Proportional (MMP) electoral parliamentary system. Labour Prime Minister Jacinda Ardern formed a coalition government with the New Zealand First Party with Green Party support following the November 2017 election.