Europe stands on the brink of “civilizational erasure” thanks to mass migration and the loss of “national identities and self-confidence”, Donald Trump’s White House has warned. A new National Security Strategy published by the President said: “Should present trends continue, the continent will be unrecognizable in 20 years or less.”

It attacked “mass migration” for increasing crime and weakening social cohesion, saying the prospect of some Nato members “become majority non-European” threatened the future of the military alliance. The document also committed the US to “cultivating resistance” within European nations to the current direction of their countries, in an explicit pledge to interfere in the internal politics of America’s allies.

While the strategy accused the European Union of undermining political liberty and sovereignty, references to Europe appear to include the United Kingdom, despite Brexit.

Publishing the strategy, Mr Trump said: “This document is a roadmap to ensure that America remains the greatest and most successful nation in human history.”

The strategy warned: “Over the long term, it is more than plausible that within a few decades at the latest, certain NATO members will become majority non-European. As such, it is an open question whether they will view their place in the world, or their alliance with the United States, in the same way as those who signed the NATO charter.”

And while it highlighted Europe’s dwindling share of the global economy, it continued: “This economic decline is eclipsed by the real and more stark prospect of civilizational erasure.

“The larger issues facing Europe include activities of the European Union and other transnational bodies that undermine political liberty and sovereignty, migration policies that are transforming the continent and creating strife, censorship of free speech and suppression of political opposition, cratering birthrates, and loss of national identities and self-confidence.”

However, the strategy said Europe “remains strategically and culturally vital to the United States”.

Committing the US to continuing to work with Europe, it said: “We want to support our allies in preserving the freedom and security of Europe, while restoring Europe’s civilizational self-confidence and Western identity.”

Setting out the US priorities for the years ahead, the strategy said these include “cultivating resistance to Europe’s current trajectory within European nations”.

It also said “a core interest” of the United States was to end the war in Ukraine quickly.