This project was already known for some time, just without too many details.
Now it has been revealed that the tower will be 210m tall, construction will start in 2019, it will be completed 5 years later. The developer is Mori Trust. It replaces the Akasaka Twin Towers, which were demolished a couple of years ago.
http://www.kantei.go.jp/jp/singi/tiiki/kokusentoc/tokyoken/tokyotoshisaisei/dai13/shiryou.html
http://www.kantei.go.jp/jp/singi/tiiki/kokusentoc/tokyoken/tokyotoshisaisei/dai13/shiryou1.pdf
Google Earth with the old buildings being demolished
June 2017

IMG_2623 by Momo1435, on Flickr
Now it has been revealed that the tower will be 210m tall, construction will start in 2019, it will be completed 5 years later. The developer is Mori Trust. It replaces the Akasaka Twin Towers, which were demolished a couple of years ago.
http://www.kantei.go.jp/jp/singi/tiiki/kokusentoc/tokyoken/tokyotoshisaisei/dai13/shiryou.html
http://www.kantei.go.jp/jp/singi/tiiki/kokusentoc/tokyoken/tokyotoshisaisei/dai13/shiryou1.pdf

Google Earth with the old buildings being demolished
June 2017

IMG_2623 by Momo1435, on Flickr