Approximately half of the British population would approvingly endorse the establishment of a European army, which would involve the United Kingdom. However, Reform UK supporters tend to align their stance more closely with the United States and oppose this idea.

Source: https://www.euronews.com/my-europe/2025/03/25/as-eu-defence-spending-surges-would-brits-support-the-creation-of-a-european-army