Just one day after polls which gave Geert Wilders’s insurgent populist party a nine-point lead on the ruling conservatives, Dutch Prime Minister Mark Rutte has drifted again politically closer to the rival he last week ruled out a coalition with.

Borrowing heavily from rhetoric commonly employed by Mr. Wilders, Prime Minister Rutte took out a full page advert and spoke in an interview with Dutch daily Algemeen Dagblad to tell migrants they should integrate or leave, and to issue a call for a return to “common decency”. He wrote:

“I tell everyone. If you don’t like it here in this country, get out, get out! That’s the choice you have. If you live in a country where the ways of dealing with others annoys you, you have a choice, go away. You do not need to be here.”

Pointing out particular “anti-social behaviour[s]” that offended, Mr. Rutte pointed to those who behave badly on public transport and in the streets, and those people who “misuse our freedoms to spoil everything, when they have come to our country for freedom”. He also condemned those who “don’t want to adapt… who attack gay people, shout at women in short skirts, or call ordinary Dutch people racist”.

The Dutch prime minister was also on a campaign against lower-order antisocial behaviour and recalled a time where he called out a man with his son on the street because they threw some rubbish onto the pavement rather than into the bin.

Mr. Rutte said these problems had been coming for a long time, but were being exacerbated by immigration. He said: “It is an insidious process that has been underway in our society for years.

“There have always been people who exhibited deviant behaviour. But something has come to pass in the last year where we as a society should have an answer. With the arrival of large groups of refugees, the question arises: will the Netherlands still be the Netherlands?”

Although he did not mention Mr. Wilders in the paper, the remarks have been interpreted as an attempt to win back voters from the populist right. Mr. Wilders responded to the advert on Monday, reminding voters that despite his words, Mr. Rutte has presided over “open borders, the asylum tsunami, mass immigration, Islamisation, lies and deception” in his years in government.

Mark Rutte: de man van de open grenzen, de asieltsunami, de massaimmigratie, de islamisering, de leugens en het bedrog.#gazelfwegrutte https://t.co/ruNj9wC4XO — Geert Wilders (@geertwilderspvv) January 23, 2017

Het origineel is altijd beter. pic.twitter.com/oVGVhWwMWF — Geert Wilders (@geertwilderspvv) September 9, 2016

Despite his freshly critical attitude towards the social habits of new migrant arrivals, Mr. Rutte last week totally ruled out the possibility of going into coalition with Freedom Party leader Mr. Wilders, the Netherlands’ most strident anti-mass-migration campaigner. Mr. Wilders’s party has more than doubled from 15 points since the last election and, if present polls are borne out, will lead the largest party in March.

Characterised by a large number of special interest parties rather than two or three major parties as seen in countries like the United Kingdom, France, and the United States, the Netherlands has never had a majority government since the end of the Great War in 1918.

If Mr. Rutte follows through with his “zero” chance comments, it could scupper not just Mr. Wilders’s chances of getting into government but also his own, and pave the way for a minority administration of left-wing and centrist parties capable of outvoting a significantly diminished conservative party which scraped through by just three percentage points in 2012.

The newspaper advert taken out by the prime minister comes just days after a major speech by Mr. Wilders at a European populist conference in Germany, where he said his allies were working to “make Europe great again” and predicted electoral victories for both himself and French counterpart Marine le Pen.

In a speech that repeatedly questioned how Europeans could shape a continent fit to pass down to their descendants, Mr. Wilders said: “How do we protect our values? How do we protect our civilisation? Our culture? The future for our children? These are the fundamental questions we have to answer. In recent years, our governments have brought in millions, without controls, into our countries.”