UK and Japan sign defence deal of the century

Rishi Sunak and Japanese prime minister Fumio Kishida have signed an agreement allowing the UK to deploy forces in Japan and vice versa. Hailed as the most important defence pact between the two nations in over a century, the move follows a similar deal between Japan and Australia amid growing Japanese concern over aggression from China.

The deal signed at the Tower of London on Wednesday is Tokyo’s first such treaty with a European nation. Although it still needs to be ratified by both countries’ parliaments before taking effect, it will allow the UK and Japan to carry out larger, more complex military exercises and deployments.

Negotiations were at a standstill for years until both countries agreed to give each other jurisdiction over service members who caused an accident or committed a crime in their host country–meaning British troops could be hanged if they commit a capital crime in Japan.

The deal “cements our commitment to the Indo-Pacific,” said Sunak. “In this increasingly competitive world, it is more important than ever that democratic societies continue to stand shoulder to shoulder.”

While his statement made no mention of competition with China, it’s likely to have been on his mind. The treaty forms part of a defence and foreign policy "tilt" by the UK towards the Indo-Pacific after a 2021 integrated review in 2021 revealed China’s growing impact in the area.

If China were to start a war with Taiwan, which it views as a renegade Chinese province, it would not only have major implications for Japan but also affect crucial sea trade routes for Europe.

To address the threat, Japan announced major security and defence reforms last month, including a counter-strike capability that breaks the self-defence-only principle it has held since the Second World War. Its revised National Security Strategy described China as “the greatest strategic challenge that Japan has ever faced.”

Kishida's visit was the third stop in a five-day tour of five G7 nations–France, Italy, the UK, Canada and the US–for talks with his counterpart in each country. As well as defence and security challenges, the leaders also discussed trade and the G7 response to the Russian invasion of Ukraine, aiming to pave the way for a successful G7 summit in Hiroshima this May.