https://www.forbes.com/sites/michaelshellenberger/2022/09/27/us-blew-up-russian-gas-pipelines-nord-stream-1--2-says-former-polish-defense-minister/?sh=32474d312e7d
Clearly the US (/UK) is the likely culprit. The US foreign policy elite has a long and proud history of using extreme dirty tactics against governments and political movements it doesn't like.
Russia has a strong motivation to keep the gas flowing in Nord Stream1, and have Europe start the gas flowing in Nord Stream 2.
