TOKYO - Japanese Prime Minister Shinzo Abe shuffled his Cabinet on Wednesday, adding two women and the son of a former leader to freshen his image but maintaining continuity on U.S.-oriented trade and security policies.

Abe, the longest-serving prime minister in Japan's postwar history, kept key positions in the hands of close allies at a time when he is locked in a bitter trade dispute with South Korea and as he tries to fine-tune a trade deal with Washington.

Taro Kono, who had been foreign minister, was appointed defense minister, while Toshimitsu Motegi, minister in charge of economic policy, is now foreign minister. Finance Minister Taro Aso kept his job.

Yet with just two years left on his party leadership, Abe also sought to add some new faces and keep potential challengers close.

Getting the greatest attention was the new environment minister, Shinjiro Koizumi, the 38-year-old son of popular former Prime Minister Junichiro Koizumi. He was the only appointment in his 30s in a lineup dominated by men in their 50s and older.

Expectations in the Japanese public have been high for years that the younger Koizumi is destined to be Japan's leader. Koizumi has tended to keep a distance from Abe, although both hold the conservative pro-U.S. policies of the ruling Liberal Democratic Party.

Abe told reporters that he was proud of his choices as people, mostly veterans, who will tackle reforms to keep Japan competitive in the "new era" of globalization.

On Koizumi, he said: "I have big hopes he will take up challenges with innovative ideas fitting of someone from the younger generation."

Yu Uchiyama, professor of political science at the University of Tokyo, said the appointments, besides Koizumi, showed Abe chose those who were very close to him.

"Abe wanted the popular Koizumi under his control," Uchiyama said. "This is a big step for Koizumi toward becoming future prime minister, but he will also be tested for the first time in a major way."

Also in the limelight are two new female ministers, Internal Affairs and Communications Minister Sanae Takaichi and Seiko Hashimoto, a former Olympian speedskater who was appointed minister in charge of the 2020 Tokyo Olympics.

Women in the Cabinet tend to get attention in Japan, which is criticized as lagging in promoting females in both the private sector and politics.

The nationally circulated Asahi newspaper said the Cabinet appointments showed Abe was building his successors but, at the same time, having candidates competing with each other in an effort to maintain his influence.

"A strategy to create a post-Abe fight," a front-page headline said.

By rewarding various politicians with posts, Abe has avoided a "lame duck" syndrome, in which he would be powerless during what's remaining of his party leadership, said political analyst Masatoshi Honda.

Until he came to power in 2012, Japan tended to have a "revolving door" of one leader toppled after another, partly because of recurring corruption scandals. Abe also served as prime minister from 2006 to 2007.