The UK and Poland have what is currently being described as one of the closest partnerships within NATO (GOV.UK, 2022; Martin, 2023). This research paper will examine how this relationship has developed, with a special interest in the signing of the 2017 Treaty on Defence and Security Cooperation. The 2017 Treaty encouraged cooperation between the UK and Poland in a range of areas, including multiple agreements on exchanging military equipment and training of troops. These agreements became even more relevant, and arguably essential in the context of Russia’s invasion of Ukraine in 2022. This research paper will assess how this Treaty has affected interoperability in the face of Russia’s invasion of Ukraine.

It is notable that Poland and the UK signed the Treaty on Defence and Security Cooperation (2017), despite these states being members of NATO. The signing of bilateral treaties has become a common way to reaffirm commitments between member states and address new security threats (Zima 2020, p. 43). It has been argued that it was Russia’s increasingly assertive foreign policy in the 2010s which encouraged the signing of the 2017 Treaty (Zima 2020, p. 31)