Rising political star Shinjiro Koizumi on Friday called for a deepening of the alliance between Tokyo and Washington while expressing his commitment to reforms that will help Japan cope with its rapidly aging population.

"I am absolutely convinced that Japan will remain a reliable partner for the United States and for the world," Koizumi, a lawmaker from the ruling Liberal Democratic Party, said in a speech in Washington.

With the rise of China leading to a shift in the regional balance, Koizumi said there will be room for further collaboration between Japan and other democratic countries in the Indo-Pacific, such as the United States, India and Indonesia.