Does the agreement on 100-year partnership with UK offer guarantees for Ukraine?
On 16 January, Ukraine and the UK signed a historic agreement for a 100-year partnership aimed at deepening security ties and strengthening cooperation for future generations. This new agreement effectively expands Kyiv-London cooperation in the field of security, extending its timeframe from a decade to a century.
Read more to understand the political and legal obligations introduced by the Ukraine-UK century declaration in the article by Daria Cherniavska, Dmytro Sherengovsky and Sergiy Sydorenko – Military bases, mutual defence and more: what Ukraine gains from the century agreement with UK.
The agreement covers cooperation in security and defence, maritime affairs, economy, energy, justice (including international law), countering disinformation and more.
Most specifics related to security and other issues are outlined in a separate bilateral document called the Declaration on Century Partnership. The 100-year Partnership Declaration is politically framed as part of the broader Agreement on the Century Partnership, but legally, this document is not tied to the agreement and does not require ratification.
The agreement itself, according to presidential advisor Ihor Zhovkva, is subject to ratification.
As outlined in the declaration (not in the main body of the agreement), the United Kingdom pledges to provide Ukraine with annual military assistance of at least £3 billion until the 2030-31 fiscal year.
Among the political commitments by the UK listed in the declaration is strengthening the fighter jet coalition. To achieve this, London promises to invest more effort in language training for Ukrainian specialists and to "assist partners in increasing the number of F-16 jets for Ukraine" (the form this assistance will take is not specified, and the British Air Force does not operate F-16s).
Additionally, Ukraine and the United Kingdom agreed to "deepen cooperation" regarding long-range weaponry, air defence systems, and other areas.
The most intriguing provision, which could evoke a strong reaction from the aggressor state, is that the UK does not rule out the possibility of establishing military bases in Ukraine, although this is presented as a purely theoretical possibility.
This provision in the declaration is currently presented as a theoretical possibility. The specifics regarding the placement of potential military bases remain unclear.
The Century Partnership Agreement also envisions closer collaboration in the defence industry.
Priorities include:
– Joint production of weapons and ammunition,
– Establishing joint defence enterprises and innovations,
– Expanding defence industry capacities within Ukraine.
As part of the maritime capabilities coalition, the UK has also pledged to assist Ukraine in building balanced naval forces.
The declaration further establishes mutual security commitments: in the event of an attack by a third country, urgent consultations are to be held within 24 hours. Additionally, the joint declaration outlines the creation of flexible rapid-response mechanisms, including the establishment and joint use of military formations and other specialised structures for mutual defence.
NATO is also addressed in the agreement (and elaborated on in the declaration). The United Kingdom explicitly acknowledges that NATO membership is the best security guarantee for Ukraine and supports Ukraine's irreversible path toward joining the Alliance. Furthermore, one article of the agreement declares the goal of reaching consensus on Ukraine’s NATO membership.
Overall, the Century Partnership Agreement between Ukraine and the United Kingdom should be seen as an expansion and refinement of the bilateral security agreement signed in January 2024.
Now, this formalided cooperation is intended to be truly long-term, a century-long duration is highly unusual in international relations and underscores the genuinely strategic nature of this partnership.