Abe resigns, but commits to staging Olympics

Japan's longest-serving prime minister, Shinzo Abe, on Friday said Japan remains committed to "fulfill responsibilities" as host nation for the Olympic Games next year, after announcing his resignation.

"We have to make an environment where all the athletes from around the world can compete in their best condition" he said during an evening news conference.

He said his successor will likewise be committed to hosting the Games.

Concerns about Abe's health began this summer and grew this month when he visited a Tokyo hospital two weeks in a row for unspecified health checkups.

He is now on a new treatment that requires IV injections, he said.

While there is some improvement, there is no guarantee that it will cure his condition and so he decided to step down after treatment Monday, he said.

He said his health problem was under control until earlier this year but was found to have relapsed in June when he had an annual checkup.