On February 19, 2026, reports emerged that the UK is blocking the US from using its military bases, particularly RAF Fairford in Gloucestershire and Diego Garcia in the Chagos Islands, for any potential military operations against Iran. This decision reflects the UK’s apprehensions regarding compliance with international law and its desire to avoid entanglement in military conflicts.

As the US has increased military assets in the region, including aircraft carriers and warplanes, President Donald Trump reportedly discussed possible military actions against Iran with UK Prime Minister Keir Starmer. Trump has suggested that should Iran refuse to negotiate a nuclear deal, military strikes may be necessary, potentially utilizing these bases.

A UK government spokesperson emphasized the ongoing political process concerning Iran, stating that "Iran must never be able to develop a nuclear weapon," and reiterated the UK's commitment to regional security. However, the UK has not prepared to support any US offensive operations and has deployed its own military assets to bolster defenses, including six F-35 warplanes to Cyprus and four Typhoon jets to Qatar.

This situation has created friction between the two allies. Trump has publicly criticized Starmer’s efforts regarding the Chagos Islands, a strategic chain of islands that includes Diego Garcia, which the UK plans to lease back to Mauritius while retaining control for military purposes.

The UK and US have a longstanding agreement requiring British approval for any military actions launched from UK soil, which has not yet been granted concerning potential strikes on Iran. The diplomatic tension underscores the complexities of international military cooperation and the challenges of addressing nuclear proliferation in a volatile region.