With Donald Trump set to take office Jan. 20, Japan and other Asian countries are closely watching his stance on the region's alliances, looking for reassurance on U.S. security commitments.

While Trump may request that Japan increase its share of the costs of stationing U.S. forces in the country, as he pledged during the election campaign, he and Prime Minister Shinzo Abe are expected to affirm the importance of the Japan-U.S. relationship.

The two countries have agreed to "deepen and expand" their alliance, Abe adviser Katsuyuki Kawai said Friday in Washington after meeting with Michael Flynn, the incoming U.S. national security adviser.