Buildings should make people happy, the freshly crowned winner of this year's Pritzker Architecture Prize, Japan's Riken Yamamoto, said Thursday.

"My long-term objective is to design architecture that can bring joy to people around it, not only to my clients," an emotional Yamamoto told reporters in Tokyo.

"Now seeing you reporting on me like this, I feel it's okay to accept that I am a good architect," the 78-year-old said after fighting back tears.

Yamamoto was named on Tuesday as Japan's ninth winner - no country has more - of the Pritzker, seen as architecture's highest honour.

Yamamoto won "above all for reminding us that in architecture, as in democracy, spaces must be created by the resolve of the people," the Pritzker citation said.

His projects are credited with promoting human contact, such as the Koyasu Elementary School in Yokohama where terraces connect every classroom and encourage its 1,000 pupils to mix.

His transparent Hiroshima Nishi Fire Station gives the public a peek at the fire engines and personnel inside while the Yokosuka Museum of Art makes visitors feel immersed in the natural scenery.

Born in Beijing but growing up in Japan, other works include The Circle complex at Zurich Airport in Switzerland and the Tianjin Library in China, full of light with huge walls of books.

Other Japanese winners of the Pritzker, first awarded in 1979, include Kenzo Tange in 1987, Fumihiko Maki in 1993, duo Kazuyo Sejima and Ryue Nishizawa in 2010 and Arata Isozaki in 2019.

"Almost 20% of our laureates are from Japan, which is the most of any nationality in the world," said Tom Pritzker, whose father Jay Pritzker of the Hyatt hotel chain started the award.

"Having spent a lot of time in Japan, what I suggest (as the reason) is Japanese culture's relationship to nature that enables this sort of sensitive contribution that Japanese architecture has made," he said at Thursday's event at the US embassy in Tokyo.