What is the purpose of the agreement?

The new 100-year partnership between the UK and Ukraine builds upon existing agreements between the two countries and aims to “deepen security ties and strengthen partnership for future generations”.

The agreement comes at a time when future US support for Ukraine is uncertain.

What agreements are already in place between the UK and Ukraine?

Several agreements already underpin the UK’s relationship with Ukraine, including:

The previous government described the Agreement on Security Co-operation, which gave long-term security guarantees to Ukraine, as “the first step in developing an unshakeable hundred-year partnership between Ukraine and the United Kingdom.

What does the new agreement comprise?

The 100-year partnership agreement comprises:

The political declaration is made under article 11 of the treaty, which allows for further agreements or arrangements to be made “as necessary and appropriate” to implement the partnership agreement. Political declarations in themselves are not legally binding.

What does the agreement focus on?

Described by the government as “historic”, the “mutually beneficial partnership” consists of nine ‘pillars’ with a focus on areas including:

Defence and security

The agreement builds upon existing military support to Ukraine, and the provisions on security cooperation set out in the 2024 agreement. Further to the 2024 agreement, the partnership declaration envisages:

  • creating joint defence capability projects and defence industrial enterprises
  • creating “flexible rapid response mechanisms”, including military formations to respond to “challenges” that may arise in either country
  • assessing options for establishing and maintaining military infrastructure in Ukraine, including military bases, logistics depots, storage facilities and war reserve stockpiles
  • establishing a new maritime security partnership to ensure safety of navigation and the protection of trade in the Baltic, Black and Azov Seas, including operational cooperation through joint taskforces, where appropriate

The political declaration also reiterates the government’s commitment to providing £3 billion a year in military assistance until 2030/31, and to support Ukraine “for as long as needed”.

While the agreement leaves long-term military support open ended, it does not commit the government to annually providing Ukraine with £3 billion of military assistance for 100 years.

Economy, trade and scientific advancement

Trade and economic cooperation across a range of sectors, including financial services, transport and infrastructure, aims to build on the 2020 Political, Free Trade and Strategic Partnership Agreement.

An economic recovery programme will aim to reduce Ukraine’s reliance on humanitarian aid and help build economic resilience.

A new Grain Verification Scheme will aim to track stolen grain from Ukraine’s occupied regions, and scientific and technology partnerships will be established, or advanced, in healthcare, disease prevention, agri-tech, space and drones.

The UK will also be a preferred partner for Ukraine’s energy sector, including on projects developing:

  • renewable energy sources
  • a critical minerals strategy
  • green steel production

Social and cultural ties

One of the main aims of the partnership is to build long-term socio-cultural ties and exchanges through education, sport, media and the arts.

To facilitate cooperation, mobility will be improved and barriers to travel between the two countries will be removed.

A Ukrainian-British Cultural Commission will work to preserve Ukraine’s cultural heritage.

Does the treaty oblige the UK to defend Ukraine in the event of future aggression?

The agreement does not contain a mutual defence clause akin to NATO’s Article 5 provisions.

Reiterating the 2024 Agreement on Security Co-operation, in the event of aggression from a third party both countries will consult “within 24 hours” and commit to providing “swift and sustained” security assistance, military equipment as necessary and economic support. It does not oblige either party to deploy military forces.

During his visit to Kyiv in January, where the agreement was signed, Prime Minister Keir Starmer indicated that he was willing to consider deploying British forces to Ukraine as part of a wider peacekeeping force if a peace agreement were negotiated with Russia. The agreement makes no specific reference to peacekeeping forces, however.

What are the reactions to the agreement?

Some commentators have said that the agreement is significant in terms of its longevity.

Sir Bernard Jenkin MP (Con) said that the agreement sends a message of solidarity at a time when US support for Ukraine under President Trump is uncertain.

However, Ian Proud, a former British diplomat and author of a book critical of the UK’s diplomatic approach to Russia, said the agreement is “meaningless” and criticised it for containing “nothing new” beyond pre-existing agreements.

Russia’s Foreign Ministry called the agreement “null and void” and a “PR step” on the way to making Ukraine “a new British colony”.  The Kremlin said any cooperation on establishing military infrastructure in Ukraine was a “worrying element” and criticised references to a UK-Ukrainian maritime security partnership partly focused on the Sea of Azov, which Russia considers to be an internal sea.


About the author: Claire Mills is a researcher at the House of Commons Library.

Photo by: Vladimir Yaitskiy.  Licensed under CC BY 2.0