The end of the Turnberry truce: how the EU should react to US coercion over Greenland

The latest round of tariff threats from President Donald Trump, targeting eight European countries over their resistance to the idea of a United States takeover of Greenland, seeks to divide the European Union. Among the countries in Trump’s sights, six are EU members that have sent troop contingents to Greenland as a signal of solidarity with Denmark. They would face a tariff increase of 10% as of 1 February 2026 and 25% from 1 June. It is difficult to think of a clearer case of economic coercion in breach of international law.

If the threat materialises, it would also breach the so-called US-EU Turnberry agreement on tariffs reached in August 2025. On the EU side, this is being implemented via a regulation that would eliminate tariffs on all industrial imports from the US. It is therefore fitting that, in the wake of Trump’s threats, the European Parliament has stalled approval of the regulation.

A US breach of Turnberry would also justify lifting the suspension of countermeasures adopted by the EU in July 2025 against previous Trump tariffs. The countermeasures involved a tariff surcharge of 10% to 30% on €95 billion of EU imports from the US (excluding products for which the EU depends on the US) and were set to apply export restrictions on steel and aluminium scrap. The suspension of countermeasures took effect after Turnberry but expires on 7 February, unless the European Commission proposes its extension.

But responding to the US coercive threat should go beyond reintroducing measures agreed last year. Trump’s threats should be treated as coercion in the context of the EU Anti-Coercion Instrument (Regulation 2023/2675, ACI) – a step that formally requires a qualified majority in the Council of the EU.

Activating the ACI would give the European Commission more power to respond to US threats. Even just triggering the instrument would signal that the EU is united in responding to a threat to the territorial integrity of one of its members and to the fundamental values on which the international order is based. Conversely, failure to invoke the ACI would indicate that the EU will never be able to provide a united response to coercion, or that it will apply double standards depending on the identity of the coercer.

The ACI will help in responding to ‘escalation dominance’. The US might react to the EU reactivation of last year’s tariff package by extending 25% tariff surcharges to all EU countries and by adopting additional economic coercive measures. The ACI would authorise the Commission to prepare further countermeasures, such as additional tariff surcharges, export restrictions or the exclusion of US firms from EU public procurement.

The Commission should already start to discuss with EU governments which additional measures would maximise political leverage while limiting risks to the EU economy. This should allow for graduated responses in the light of the possibly changing US political context in the run up to the November 2026 mid-term Congressional elections and the fact that there is no support in the US for aggressive action against US allies.

Another important development should also be taken into account. The US Supreme Court is due to rule before February on the legality under the US International Economic Emergency Powers Act (IEEPA) of Trump’s tariffs. An EU optimist might hope that the Court will rule out the use of tariffs under IEEPA and consequently the Trump tariffs over Greenland will never materialise.

However, the Supreme Court ruling may be narrower and the US might seek to differentiate its ‘Greenland’ tariffs from other forms of tariffs it has implemented. In any case, the EU cannot depend on the vagaries of the US legal process. EU leaders meet on 22 January and must give the right political signals to enable both the reimposition of last year’s EU tariffs and export restrictions on the US and the start of ACI procedures. Such measures would of course be avoided if the US backtracks from its Greenland tariff threat and instead engages in good-faith discussions to address security concerns.

A final question is how all this might affect ongoing transatlantic cooperation on the war in Ukraine. It could be argued that the EU should uphold Turnberry because it should sacrifice economic interests to ensure US support in the defence of Ukraine. However, the situation now is fundamentally different from last year. What is at stake over Greenland is not economic interests, but the territorial integrity of an EU and NATO member. Moreover, the EU’s capacity to help Ukraine defend itself has increased significantly and there is a limit to how far the US could disengage from Ukraine without harming its own economic and political interests.