European Council President Antonio Costa said on Monday that while disagreements with the United States are normal, the new National Security Strategy released by the administration of US President Donald Trump crosses a line by threatening to interfere in Europe's internal political affairs.

Published last week, the strategy paper casts Europe as overregulated and susceptible to "civilizational erasure" via immigration, and says Washington will seek to "cultivate resistance to Europe's current trajectory" within European nations.

The plan has drawn some criticism within the EU.

"The United States remains an important ally, the United States remains an important economic partner, but Europe must be sovereign," Costa told a news briefing in Brussels, Belgium.

"What we cannot accept is the threat to interfere in European politics."

The strategy paper said it sees the growing influence of "patriotic European parties" as a cause for "great optimism".

"The United States cannot replace European citizens in choosing which parties are good and which are bad," said Costa.

The council president, who chairs summits of the bloc's 27 national leaders, acknowledged long-standing differences with the Trump administration, but said the new strategy "goes beyond that".

Costa criticized sections of the strategy that appeared to denounce the EU's efforts to hold US tech giants accountable for the spread of disinformation and hate speech online.

The former Portuguese prime minister emphasized that the EU and the US hold different views on freedom of speech.

"The United States cannot replace Europe in what its vision is of freedom of expression," he said.

"There would be no freedom of speech if citizens' freedom of information is sacrificed to defend the techno-oligarchs in the United States."

Analysts told The Guardian newspaper that the document codifies a US strategy previously outlined by US Vice-President JD Vance: "It transposes that doctrine into an officially backed state line," said Nicolai von Ondarza of the German Institute for International and Security Affairs. "It really represents a fundamental shift in transatlantic relations."

EU-US ties worsened after the EU fined Elon Musk's X platform $140 million last week. Musk said on Sunday the EU should be "abolished and sovereignty returned to individual countries".

On Saturday, US Deputy Secretary of State Christopher Landau called the EU "unelected, undemocratic, and unrepresentative", saying it undermines US security.