United States President Donald Trump has doubled down on his attacks against Europe, arguing that the continent is now “weak” and “decaying” due to migration.

Trump told the publication Politico on Tuesday that European nations should deport people who “came into the country illegally”.

“Europe, they want to be politically correct, and it makes them weak,” Trump said.

The US president has long opposed immigration to Western countries, often using harsh rhetoric to target immigrants, specifically from African and Muslim-majority countries.

“Europe is a different place. If that keeps going the way it’s going, in my opinion, many of those countries will not be viable countries any longer,” Trump said. “Their immigration policy is a disaster.”

Trump’s comments come less than a week after his administration released a National Security Strategy berating Europe and warning of “civilisational erasure” on the continent.

The document called for “cultivating resistance to Europe’s current trajectory within European nations”.

Asked about the possibility of interfering in Europe’s internal affairs, Trump said he is focused on governing the US. However, he did not rule out endorsing candidates and parties in European elections, akin to his support for right-wing politicians in Latin America.

Trump also confirmed that his Hungarian ally, Prime Minister Viktor Orban, is seeking a US bailout, similar to the $40bn aid package that Washington handed to the government of Argentinian President Javier Milei.

But the US president denied Orban’s claim that an assistance deal has been secured.

It may be difficult for the US to empower allies beyond Hungary. Many European far-right parties that echo Trump’s rhetoric have been shunned in their own countries.

In Germany, for example, groups across the political spectrum have vowed not to include the hard-right Alternative for Germany (AfD) party in any governing coalition.

In 2017, during his first term, Trump sparked a diplomatic crisis with the United Kingdom when he shared fake videos from a British far-right leader that purported to paint Muslim immigrants as violent.

Then-UK Prime Minister Theresa May called the posts “wrong”, and several politicians condemned the US president.

On Tuesday, Trump renewed his attacks on one of his most frequent political targets – London’s Mayor Sadiq Khan.

The US president questioned Khan’s ideology and suggested that the mayor, a Muslim, was elected by immigrants, echoing the “great replacement” conspiracy theory that alleges an unfounded plot to replace white voters with newcomers.

“If you take a look at London, you have a mayor named Khan. He’s a horrible mayor. He’s an incompetent mayor, but he’s a horrible, vicious, disgusting mayor,” Trump said.

Although the UK has been adopting restrictive immigration laws, Trump claimed that it is “allowing people just to come in, unchecked, unvetted”.

“Look at the mayor of London. He’s a disaster. He’s a disaster,” Trump said. “He’s got a totally different ideology of what he’s supposed to have. And he gets elected because so many people have come in, and they vote for him.”

Trump also attacked Khan during his speech at the United Nations General Assembly in September, suggesting that the London mayor adopted Islamic law in the city.

The US president’s rhetoric against Khan and Europe has been met with a muted response over the past weeks.

UK Prime Minister Keir Starmer has only defended and voiced support for Khan – his Labour Party ally – without condemning or directly criticising Trump.

In his Politico interview, Trump also decried the state of Paris – a major destination for US tourists – as well as Sweden, saying that the Nordic country is now “very unsafe”.

Sweden, home to around 10.6 million people, had 92 homicides last year – far less than half of the 250 murders recorded in the US city of Memphis, which has a population of less than 630,000 people.