Dutch Prime Minister Mark Rutt gives an interview during the World Economic Forum in Davos, Switzerland, on Thursday. (Simon Dawson/Bloomberg News)

Facing an upcoming electoral challenge from a populist far-right party, Dutch Prime Minister Mark Rutte released an open letter Monday that offered a thinly veiled warning to immigrants: “Act normal or go away.”

Rutte's letter was published in a full-page newspaper advertisement and promoted on social media by his party, the center-right People’s Party for Freedom and Democracy (VVD).

In his message, the prime minister said he understood there were growing concerns in the Netherlands about those coming into the country who don't integrate. “People who don't want to adapt, [who are] attacking our habits and rejecting our values,” Rutte wrote, “who attack gay people, who shout at women in short skirts, or call ordinary Dutch people racist.”

“I understand the people who think that if you so fundamentally reject our land, I prefer that you leave,” the letter said. “As it happens I have that feeling too. Act normal or go away.”

Rutte repeated his message in a separate interview with the AD newspaper, saying that those who do not agree with Dutch values should leave. “You have the choice, go away!” the prime minister said. “You do not need to be here!”

The Netherlands is preparing for nationwide elections to be held on March 15. Rutte, who has held the office of prime minister since 2010, is facing a battle for right-wing voters from Geert Wilders, the outspoken anti-immigration politician who leads the Party for Freedom (PVV).

Wilders has capitalized on a populist backlash to refugees and migrants in the Netherlands over the past few years, and some recent polls have shown support for the PVV nearly equal to VVD ahead of the vote. The populist leader would struggle to form a coalition even if his party won a large amount of votes, however. Most mainstream parties, including the VVD, have refused to work with Wilders, who was recently convicted of insulting an ethnic group and inciting discrimination after he led chants against Moroccans.

Rutte's letter didn't mention Wilders by name, but it did appear to mildly criticize the PVV's rhetoric, arguing that “the solution is not [to] blame a group of people because of one person's actions.” Among observers, however, the prime minister's message was widely interpreted as an attempt to appeal to Wilders's supporters ahead of an increasingly competitive election.

Cas Mudde, a Dutch political scientist at the University of Georgia who studies the European populist radical right, said Rutte was trying to show right-wing voters that he could be as tough on immigration and law and order as the PVV. “It is thinly veiled nativism, completely ignoring the anti-refugees violence, physical and verbal, by natives that the country has experienced in the past years,” Mudde said.

Wilders responded to Rutte's letter with a flurry of tweets Monday, accusing the prime minister of stealing his positions. Wilders also suggested that Rutte was being hypocritical, as he was “the man of open borders, the asylum tsunami, mass immigration, Islamization, lies and deception.”

Amar Nadhir contributed to this report from The Hague.

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