Prime Minister Shinzo Abe and his British counterpart, Theresa May, have agreed to preserve free trade, while stepping up cooperation to pressure North Korea on its nuclear and missile programs.

At a meeting in London on Friday, they also agreed to work together to have a successful Group of Seven summit, set to be held in Italy next month.

"With a protectionist movement becoming prominent in the world, Japan and Britain must hoist the flag of free trade high in step with the United States," Abe said at a joint news conference with May. "It is important to the global economy that Britain's withdrawal from the European Union take place in a smooth manner."

Abe appealed to May to minimize the effects of the withdrawal on Japanese companies doing business in the region, Japanese officials said.

Since the shock June 23 Brexit vote, Japan has expressed unusually strong public concerns about the impact it will have on the United Kingdom, the second most important destination for Japanese investment after the U.S.

Considering China's maritime assertiveness, Abe and May agreed on the need for freedom of navigation to ensure the Indian and Pacific oceans remain free and open, the officials said.

They also agreed to promote bilateral security cooperation, including conducting joint training by the Self-Defense Forces and the British military, as well as countering terrorism, they said.

Abe said North Korea's nuclear and missile programs, along with tensions in the East and South China seas, pose threats to the international order, adding that Japan and Britain will work hand-in-hand on such issues.