Ukraine War, May 16, 2022: “Pacta sunt servanda”–Britain threatens to undermine international legal order by violating U.K.-EU Protocol on Irish border

To see a list of previous articles, enter “Ukraine” in the Search Box on the upper right, on The Trenchant Observer web site, and you will see a list in chronological order.


1) Lisa O’Carroll, “Brexit protocol row: what are the issues dividing UK and EU?; British government is threatening to override Northern Ireland rules if bloc does not show ‘requisite flexibility,'” The Guardian, May 16, 2022 (15.10 BST);

2) Suzanne Lynch, “Irish foreign minister: UK in for ‘very difficult summer’ if it overrides Northern Ireland protocol; Simon Coveney says EU willing to reduce customs checks in NI if it gets more access to Britain’s border trade data,” Politico, May 16, 2022 (11:10 am);


3) David Collins, “No, Britain is not breaking international law on the NI Protocol; Article 16 of the treaty allows us to take appropriate measures in response to the EU’s unreasonableness, The Telegraph, May 19, 2922 (6:00 pm).


One of the most fundamental norms of international law, restated by Hugo Grotius some 400 years years ago, is Pacts sunt sevanda, which means “Treaties are to be observed”. This principle is restated in Article 2 paragraph 2 of the United Nations Charter.  It is set forth explicitly in Article 26 of the 1969 Vienna Convention on the Law of Treaties, as follows:

Article 26 – Pacta sunt servanda

The U.S. invasion of Iraq in 2003 in flagrant violation of Article 2 paragraph 4 of the United Nations Charter greatly weakened that norm. The “business-as-usual response of the West to the Russian invasion of Georgia in 2008, and to the Russian invasions of the Crimea and the Eastern Ukraine in 2014, only further weakened the prohibition against the use of force. In the same fashion, the assassination of Iranian Quds Force Commander General Qasem Soleimani in Iraq in January 2020, further chipped away at the norm, as did developments such as the Turkish invasion of northeastern Syria in 2019, and other actions by Israel and Egypt.

Each violation weakens international law.

Britain’s potential violation of the principle of pacts sunt servanda by not honoring the U.K.-EU Protocol on the Irish border may seem like a small matter.

However, if Britain can violate its treaty with the EU on the Irish border, what country will not be able to find equally compelling arguments to violate one of the agreements it has solemnly entered into and is bound by international law to perform in good faith?

Moreover, how would such an action strengthen, or weaken, the efforts of the West to defend international law and the international legal order by opposing Russia in Ukraine?

The Trenchant Observer