When Toshihiro Soejima, the director of The Genron NPO, began his annual fundraising efforts for the Beijing-Tokyo forum this year, he was worried "we won't be supported by companies".

He had reason for his pessimism about the forum, which is co-sponsored by the nonprofit Genron NPO and China Daily newspaper in China every year.

Relations between Asia's two giant neighbors have been hit hard by their territorial dispute since September 2012, with polls indicating mutual goodwill has dropped to a record low for the past decade.