Foreign Minister Winston Peters said "this is a whole new world", on his first visit to the United States since Donald Trump became the 47th president.

Peters' visit comes at a time of great change for the United States.

In recent months, the country has entered into a trade war with some of its closest allies, such as Canada, threatened tariffs on much of the world — including New Zealand — and flipped its foreign policy position on the war in Ukraine.

The rapid changes have caused concern, particularly for Kiwi businesses, with America now New Zealand’s second-largest trading partner.

"This is a whole new world," Winston Peters told 1News in New York.

"[It’s] something we've never seen before in terms of the American policy. We need to understand it and understand that the time to make a decision is when the dust settles."

Peters is expected to meet with one of the US President’s highest-ranking officials, secretary of state Marco Rubio, in Washington DC next week.

"I'm wanting to ensure that we in New Zealand don't overreact, don't over respond too soon," he said.

"We've been allies and friends of the United States for a long, long, long time."