The first revision of the U.S.-Japan Defense Guidelines in 17 years will "transform" the bilateral alliance, U.S. Defense Secretary Ashton Carter said Wednesday, April 8, according to the Associated Press.

The guidelines, expected to be formally approved in about three weeks, "will help us respond flexibly to the full scope to the challenges we face, both in the Asia-Pacific and around the globe," he said at a news conference after meeting his Japanese counterpart in Tokyo.

Carter, who travels to South Korea later this week, is on his first trip to Asia since becoming defense secretary in February.

Japanese Defense Minister Gen Nakatani said that he and Carter also agreed that relocating a U.S. Marines base in Okinawa to another part of the island is the "only solution" to closing the existing base, which lies in a heavily populated area.

Many in Okinawa, and their current governor, oppose the construction of the replacement base in a less populated area, arguing that the facility should be moved off Okinawa entirely.

The defense guidelines are expected to lay out the framework for Japan to play a bigger role in regional security, as the government loosens constitutional restrictions on the use of its military.