"Appeasement is always a sign of weakness," Tusk wrote on X on Tuesday, adding that "Europe cannot afford to be weak," either in the face of its enemies or when pressured by an ally.
"Appeasement brings no results, only humiliation," Tusk said, arguing that "European assertiveness and self-confidence" have become a necessity.
Tusk is expected to attend a special European Union summit on Thursday focused on the growing dispute between Washington and Copenhagen following US President Donald Trump’s renewed calls for the United States to take control of Greenland.
European Council President Antonio Costa said EU member states stand united in support of Denmark and Greenland, warning that proposed US trade tariffs would harm transatlantic relations.
"The EU is ready to defend itself against any form of coercion," Costa said.
Trump earlier this month reiterated his long-standing claim that the United States should acquire Greenland, the world's largest island, and did not rule out the use of military force, calling the Arctic territory vital to US national security.
He has warned that without US action, Greenland could fall under Russian or Chinese influence.
On Saturday, Trump escalated his rhetoric, announcing that 10-percent tariffs would be imposed starting February 1 on goods from eight European countries, including Denmark.
He said the tariffs would rise to 25 percent in June and remain in place until a deal is reached to purchase Greenland, an autonomous Danish territory.
Trump linked the tariff threat to the countries' participation in joint military deployments to Greenland.
(jh/gs)
Source: PAP, Polish Radio