The UK’s withdrawal from the Energy Charter Treaty (ECT) officially took effect on 27 April 2025, which is a major step forward for climate action. But without further measures, the ECT’s “sunset clause” could still allow fossil fuel investors to sue the UK over climate policies until 2045.
This independent legal opinion, commissioned by the Trade Justice Movement and Global Justice Now, shows that the UK can act to neutralise this risk. The advice confirms that the government could enter into an “inter se agreement” with other countries also leaving the ECT to disapply the sunset clause, without the need for new legislation.
This legal route offers a credible, urgent opportunity to fully exit the ECT and protect UK climate policy from corporate lawsuits. We are calling on the UK government to work with other like-minded countries to act swiftly.
