Britain's historic decision to leave the European Union could hamper Japan's efforts on a trade deal with the EU as well as its relationship with Asian and other global partners, analysts said.

The comments Friday came as the government here described its disappointment at the exit, and British expats in Japan also reacted in shock and general disapproval.

Trade minister Mikio Haya-shi told reporters on Friday that Britain's decision "may make it hard" for Japan to reach an economic partnership agreement with the EU by the end of this year.