The threats posed by climate change call for strong action from the international community to limit carbon emissions. Before the Fukushima accident that followed the Great East Japan earthquake and tsunami on 11 March 2011, both Britain and Japan were considering an ambitious expansion of nuclear power as part of their strategy to reduce carbon emissions. However, the accident may have thrown nuclear power as a publicly accep' energy technology into doubt. This study uses several nationally representative surveys from before and after the Fukushima accident to examine how it may have changed public perceptions of climate change and energy futures in Britain and Japan. The study found that already before the accident the Japanese public were less supportive of nuclear power than the British. While British attitudes have remained remarkably stable over time, the Japanese public appear to have completely lost trust in nuclear safety and regulation, and have become less acceptive of nuclear power even if it would contribute to climate change mitigation or energy security. In Japan the public are now less likely to think that any specific energy source will contribute to a reliable and secure supply of energy. The implications for energy policy are discussed. (C) 2013 Elsevier Ltd. All rights reserved.