There is a gap in our knowledge that has not been filled much yet: the interplay between uncertainty and transparency, as well as the social amplification of risk and potential manipulation, interconnected with the media agenda-setting theory in risk communication. To fill this gap, this study investigates how China’s, South Korea’s, and Japan’s leading English-language newspapers present their respective stands on the issue of the Fukushima nuclear-treated-water discharge in the initial phase between 1 January 2021 and 31 May 2021. Discourse analysis reveals divergent discourses in the selected newspapers, with The Japan Times employing scientific evidence, discussions of radioactive emission, proactive measures, details on contaminated water treatment, treated water disposal, and counter-blaming tactics to construct the discourse of image protection; China Daily utilising arguments from the politically-driven US-Japan alliance, expert discourse on the lack of a scientific basis, and empathy for the fishery trade to create the discourse of politically-driven public health concern; and The Korea Herald using accusations of Japan’s irresponsibility, historical facts, geopolitical problems, and violations of human rights to construct the blaming discourse. The analysis also reveals the striking similarities among the three press coverages, which underpin the discourse of transnational alignment and shared concerns, highlighting environmental, human health, and economic concerns related to the fishing industry. Even though the three news outlets had different points of view, both CD and TKH focused on the lack of transparency in Japan’s handling of uncertainty in risk communication and the social amplification of risk. In contrast, TJT amplified the safety of the nuclear-treated water discharge to attenuate people’s perceptions of its risk. Theoretically, this study demonstrates the close relationship between the handling of uncertainty in risk communication and transparency, as well as the social amplification of risk and potential manipulation, with practical implications for newsrooms to communicate risks.