The coronavirus is creating bad blood between Belgium and its lowland neighbor.

As the Netherlands charts its own path on restrictions to stop the coronavirus, authorities in Belgium’s border towns are worried that the Dutch approach could spread the virus.

While Belgium has imposed a ban on all non-essential movement of people, in the Netherlands people can still move around and meet with others as long as they keep 1.5 meters apart. The Dutch government took new steps Monday evening to cancel events up to June 1 and give mayors the power to close public locations if necessary — but the Dutch measures are milder than those in much of the rest of the Continent.

"In the Netherlands, shops are still open and meetings of 100 people are still allowed — these are breeding grounds [for the virus],” Marino Keulen, mayor of the Belgian border town Lanaken, said ahead of the latest Dutch announcements.

Belgium last week brought in border checks to clamp down on non-essential travel. Keulen called the border checks a “signal to The Hague” to “quickly scale-up” its response and align with neighboring countries. After Belgian authorities put up barricades on roads, they told cars with Dutch license plates to turn around and head back home.

“The Dutch government is incompetent and ridiculous in its response to the coronavirus crisis” — Leopold Lippens, mayor of Belgian town Knokke-Heist

“The Dutch government is incompetent and ridiculous in its response to the coronavirus crisis,” said Leopold Lippens, the mayor of Belgian seacoast town Knokke-Heist, who opted to put his municipality on lockdown ahead of national restrictions. “The Netherlands is doing nothing, so we have to protect ourselves.”

Dutch Prime Minister Mark Rutte has defended the country’s approach, which last week saw schools, bars and restaurants closed. “The objective of the approach is to not overburden the health care system, as well as protect the elderly and vulnerable,” Rutte said during a parliamentary debate last week.

However, Rutte on Friday offered support to Belgium — telling a press briefing he was “very surprised” that some Dutch citizens had been traveling to Belgium to refuel their cars or for tourism.

“I’m appealing to everyone: Don’t cross the border for day trips or outings, guys, this is not business as usual,” Rutte said.

That message doesn't seem to be getting through. Last weekend, Dutch city dwellers traveled en masse to the country’s beaches and forests — prompting Dutch coastal towns to close roads, while a nature protection organization asked people to stop visiting reserves.

Pictures of crowded beaches, parks and other outdoor areas prompted medical experts and politicians to call for stricter rules to enforce social distancing. Rutte on Monday slammed the “annoying" behavior of those ignoring the rules, and said that a full lockdown would be the next step, something he said he hoped it wouldn't be necessary.

Roger van Boxtel, the CEO of Dutch public passenger rail network NS, pointedly remarked that trains were running to help essential employees get to work — not for people looking to make the most of the spring sunshine.

The Netherlands has so far recorded 4,749 positive tests for the coronavirus, and 213 people have died, according to POLITICO's live pandemic tracker. The Dutch North Brabant province, near Belgium, has been one of the hardest-hit: Almost one-third of the country's coronavirus patients live in the area.

In Belgium, the death toll stands at 122, while 4,269 people have tested positive for the virus. But “that is an underestimation because at this stage only sick people and health workers are tested,” said Steven Van Gucht, who chairs the government’s coronavirus scientific committee.

On Sunday, Dutch and Belgian authorities agreed to introduce a vignette for workers who have to cross the border, allowing them to bypass tougher controls. Border enforcement is a temporary return to something that hasn't existed among the Benelux countries since 1960.

“Inevitably, if we allow the return of tourists now … the likelihood that we’ll have more people suffering increases too” — Guy Gilloteaux, mayor of La Roche-en-Ardenne

Guy Gilloteaux, the mayor of La Roche-en-Ardenne, a popular Belgian tourist destination, said stopping visitors to his town would mean economic difficulties.

“But public health is our priority,” said Gilloteaux. “Inevitably, if we allow the return of tourists now … the likelihood that we’ll have more people suffering increases too.” Ultimately, “it’s not a measure of distaste toward others,” he said, arguing that border restrictions will prevent people in both countries from getting sick. “It’s a gesture of love.”

The mayor of Knokke-Heist was less romantic. “I don’t need the Dutch, we are very happy without them in Knokke-Heist,” said Lippens.

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