The Semantics of the Paris Agreement

 by Amy Wilson

When thinking about the choice of words in an international agreement, we may think that the nuances surrounding certain terms, such as ‘developed country’ or ‘climate finance’ — even how to encourage climate action — may be where signing Parties disagree. 

This is often true. Countries are considered to be equal during the United Nations (UN) climate negotiations [1], but their contributions to: greenhouse gas (GHG) emissions, development needs, and vulnerability to the climate crisis vary significantly. Consequently some countries, such as those that are developing and those that have contributed the least to the crisis, may resist committing to binding action that may hinder their development. The United Nations Framework Convention on Climate Change (UNFCCC) acknowledges these differences as ‘common but differentiated responsibilities and respective capabilities’ (CBDR-RC) [1]. 

The Paris Agreement approaches the differentiation between countries’ responsibilities to address the climate crisis very carefully, unlike the Kyoto Protocol, which had a rigid distinction between industrialised and developing countries (Annex I and non-Annex I) [2,3]. The Paris Agreement has subtle but important differences between subsets of countries [4].

  1. The Paris Agreement distinguishes between developed and developing countries – developing countries can increase their ambitions over time without formally graduating into an Annex I system. 
  2. Countries are also differentiated in a context-specific way – such as Least Developed Countries (LDCs) and Small Island Developing States (SIDS) for specific aspects of the agreement, for example adaptation finance, capabilities, reporting timelines and transparency.
  3. The introduction of the Nationally Determined Contributions (NDCs) and the mechanism for each country to pursue its own bottom-up climate crisis approach. This is different to the normal top-down ‘hard’ commitment approach that other international treaties have often used. This again acknowledges the differences and capabilities of the different countries. 

Alongside the subtle differences, the Party delegates also found themselves discussing (and arguing) over words such as should and shall

Why? What is the difference between should and shall

The English dictionary states that should can be ‘used to indicate obligation, duty, or correctness, typically when criticising someone’s actions’, whereas shall is defined as ‘expressing an instruction, command, or obligation’. 

The United States (US) objected to the use of shall in Article 4.4 of the Paris Agreement [5]: 

‘Developed country Parties shall (later changed to should) continue taking the lead by undertaking economy wide absolute emission reduction targets. Developing country Parties should continue enhancing their mitigation efforts, and are encouraged to move over time towards economy-wide emission reduction or limitation targets in the light of different national circumstances.’

US government lawyers stated that the choice of shall for developed countries and should for developing countries in relation to mitigation efforts, would make rich countries legally obliged to cut emissions rather than just having to try like developing countries – they asked for the wording to be altered to should rather than shall [5]. This was of particular important to the US, because they would not be able to sign a legally binding obligation to implement an emission reduction target – Congress would not approve [5]. 

This is just one example of the should-shall debate. Next time you read through the Paris Agreement (or any other UNFCCC document) think about where should and shall are used and the rigidity these terms pose for each of the country types. For example, take a look at Article 4.2 of the Paris Agreement (link to document here) and the use of shall in relation to the Nationally Determined Contributions (NDCs) [6]. 

Other words that are considered to be important when thinking about placement in UNFCCC documentation include acknowledge and recognise. You could google the definitions of these two words and think about what a statement including one of these words would mean for the signing Parties – why might a Party not want to sign? How binding might these words be for a specific topic?


[1] United Nations Framework Convention on Climate Change. Available at, (accessed 01/05/21)
[2] Kyoto Protocol to the United Nations Framework Convention on Climate Change. Available at, (accessed 01/05/21)
[3] Paris Agreement. Available at , (accessed 01/05/21)
[4] Pauw, P., Mbeva, K. & van Asselt, H. Subtle differentiation of countries’ responsibilities under the Paris Agreement. Palgrave Commun 5, 86 (2019).
[5] Norton Rose Fulbright (2016). Available at—the-paris-agreement, (accessed 21/03/21)
[6] Huffpost (2017). Available at The 4 Issues That Can Make or Break the Paris Climate Agreement | HuffPost (accessed 21/03/21)
Categories Key Terms and Agreements

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