Japan’s heavily trailed decision to discharge treated water from the Fukushima No. 1 nuclear plant into the ocean has caused significant friction with China, damaging the chances of a much-awaited detente.

As the two countries celebrate the 45th anniversary of the signing of the Treaty of Peace and Friendship, Japan is now bracing for a new period of wide-ranging tensions with its giant neighbor.

In the direct aftermath of the start of the discharge last Thursday, Beijing immediately enforced a retaliatory ban on all Japanese fish imports, while reports of harassing phone calls to businesses, schools and government facilities across Japan made headlines in the country over the weekend.