The United States and New Zealand have resumed military contacts after a hiatus of nearly 30 years, brought about by a disagreement over nuclear-powered vessels.

The defense agreement was made following a meeting at the Pentagon between U.S. Defense Secretary Chuck Hagel and his New Zealand counterpart, Jonathan Coleman.

It opens the way for the first visit by a New Zealand naval vessel to a U.S. port in more than three decades.

The two countries have been estranged militarily since 1984 when the United States issued a policy restricting visits by New Zealand warships to American ports, the American Forces Press Services reported.

The ANZUS Treaty between the United States, Australia and New Zealand was partially suspended in 1984 because of New Zealand's opposition to U.S. naval vessels that are nuclear armed or nuclear powered visiting its ports.

Relations started to thaw last year when then-Defense Secretary Leon Panetta visited New Zealand, AFPS reported.

Panetta announced an easing of restrictions on visits by New Zealand naval vessels to Defense Department and Coast Guard facilities on a case-by-case basis.

In the joint statement by Hagel and Coleman, Hagel authorized the New Zealand navy to dock at Pearl Harbor, Hawaii, during next year's RIMPAC military exercises, the New Zealand Herald reported.

The first biennial Rim of the Pacific Exercise international maritime warfare exercise was held in Honolulu in 1971 and involved forces from Australia, Canada, New Zealand, the United Kingdom and the United States.

Since then it has been hosted and administered by the United States Navy's Pacific Fleet in conjunction with the Marine Corps, the Coast Guard and Hawaii National Guard forces under the leadership of the Governor of Hawaii.

The number of participating countries has increased, as well as observer nations, over the years, but New Zealand has been notable for its absence.

"This will be the first time a New Zealand navy ship will have visited Pearl Harbor in more than 30 years," Hagel said.

The agreement with New Zealand is "another act in strengthening our relationship and the re-balance to the Pacific," he said.

Coleman said New Zealand is looking to expand defense cooperation with the United States also through peacekeeping initiatives, humanitarian assistance and disaster relief work in the Asia-Pacific region.

"Our defense relationship with the United States is in great shape and provides a strong platform for working closely together in the future," Coleman said.

"We have agreed to expand our cooperation on peacekeeping training initiatives. New Zealand also will be providing military instructors to the U.S.-led Global Peacekeeping Operations Initiative from 2014."

The United states put military cooperation on hold after Prime Minister David Lange barred nuclear-powered or nuclear-armed ships from using New Zealand ports or entering territorial waters.

Under New Zealand's 1987 Nuclear Free Zone, Disarmament and Arms Control Act, the country's territorial sea as well as its land and airspace are designated nuclear-free zones. It remains a cornerstone of the country's foreign policy.

Ships whose propulsion is wholly or partly dependent on nuclear power are barred from entering New Zealand's 12 nautical mile territorial waters.

The act also bans the dumping of radioactive waste within territorial waters. But nuclear power plants and nuclear research facilities are allowed.