"As the United States deepens its relationship with the Philippines, it's important for regional security that Japan join in," a Japanese defence ministry source with knowledge of internal discussions on national security told Reuters.
At a press briefing last week, Neil Imperial, the Philippines Assistant Secretary for Asian and Pacific Affairs, said Marcos wanted to "facilitate closer defence, security, political, economic and people-to-people ties" while in Japan.
That sentiment is shared in Tokyo, which has been deepening security ties with nations that view China with concern.
Those deals provide a framework for how Marcos and Kishida could also forge deeper military ties to counter their common adversary, say experts.
"The Philippines is a critical security partner for Japan," said Narushige Michishita, a professor at the National Graduate Institute for Policy Studies (GRIPS) in Tokyo.