Denmark weighs NATO Article 4 trigger as drone incursions disrupt Aalborg and Copenhagen airports
Danish officials consider invoking Article 4 after drones forced closures and spurred international security consultations, with Oslo and other airports affected in a wider pattern of border disturbances.
Denmark is weighing whether to trigger NATO's Article 4 after drones forced the suspension of flights at Aalborg Airport for a second time this week, a step that would prompt allied consultations on security threats.
Danish authorities said they have reached out to NATO and the European Union in the wake of the threat, according to Euronews. Copenhagen has signaled that allied discussions could be warranted as Denmark reviews the scope of the incident and potential responses. If Article 4 were invoked, it would prompt a meeting among alliance members to assess the situation and consider cooperative steps, though it does not by itself compel action.
Danish authorities described the Aalborg episode as a hybrid attack carried out by a professional actor, with the drones launched locally rather than originating from abroad, according to BBC reporting cited by Euronews. Deputy Prime Minister and Defense Minister Troels Lund Poulsen vowed that Denmark would "find the people who are behind this." He added that Denmark possesses various military capabilities, including F-35 fighters and frigates, to help defend the country. Smaller airports elsewhere in Denmark reportedly experienced drone activity but were not forced to close.
On Monday, a similar drone incident affected Copenhagen Airport. Unlike the Aalborg episode, officials indicated there were different possibilities about the origin of the disturbance, and Danish Prime Minister Mette Frederiksen called the episode the most serious attack on Danish critical infrastructure to date, noting that authorities were not ruling out any options about who might be behind it. Reuters reported her remarks as authorities pursued leads and weighed next steps.
The European dimension of the threat was underscored by comments from European Commission President Ursula von der Leyen, who said the drones that halted flights at Copenhagen airport were part of a pattern of persistent contestation at Europe’s borders, Euronews reported. In a broader regional context, the Oslo Airport in Norway was also shut down for about three hours on Monday evening due to possible drone threats, according to Euronews.
NATO has not issued public statements on the matter, a fact noted by Fox News Digital when it reached out for comment. The alliance’s status in relation to Article 4 discussions remains a focal point for Denmark as authorities gather information and determine whether to activate the consultative mechanism.
The incidents come amid a wider pattern of airspace and border contestation, with officials cautioning that the response will depend on verified attribution and evolving intelligence. The Danish government has emphasized that it will pursue those responsible and consider all options as it coordinates with its allies and neighbors.
The drone activity at Aalborg and Copenhagen follows broader security concerns raised across Europe about emerging threats to critical infrastructure and airspace. While Danish officials describe the Aalborg incident as locally launched and not Russia-originated, authorities have not ruled out any possibility as investigations continue. Oslo’s temporary closure adds to a regional picture in which several airports faced drone-related disruptions within a short timeframe.
As Denmark weighs the Article 4 option, officials stress that invoking the treaty’s consultation framework would not automatically trigger a military response but would formalize a dialogue among NATO members to assess threats and determine appropriate steps. The government has urged caution and precision as investigators seek to attribute responsibility and prevent a recurrence, while the alliance monitors the situation and coordinates with European partners.
