Dutch Prime Minister Mark Rutte sought to lure voters away from anti-immigration lawmaker Geert Wilders, as campaigning for the March 15 national elections heated up on Monday.

In a full-page newspaper message, Rutte said "we have to actively defend our values" against people who reject those values and act antisocially. "Behave normally or go away," he said.

While Rutte's message did not mention Wilders or his Party for Freedom, it was clearly aimed at winning over voters who would likely back Wilders's hard-line platform.

Rutte, leader of the centre-right People's Party for Freedom and Democracy, said he understands calls for people who don't integrate to leave the Netherlands. "I have that feeling, too," he said.

I believe we are witnessing historic times - Geert Wilders. Party for Freedom

But he also appeared to criticize Wilders' anti-immigration stance. "The solution is not to tar people with the same brush," Rutte said. A court convicted Wilders in December of insulting and inciting discrimination against Moroccans. He is appealing the conviction, which he branded "shameful."

On Monday, Wilders hit back and called Rutte "the man of open borders, the asylum tsunami, mass immigration, Islamization, lies and deception."

Rutte trails Wilders in polls

Polls give Wilders an edge on Rutte at the moment. But mainstream parties shun Wilders and it appears unlikely he will be able to form a coalition even if he wins the popular vote.

Rutte's coalition has steered the Netherlands to a strong recovery from the financial crisis that swept Europe, but his party's popularity has slipped as Wilders's has grown.

France's Marine le Pen, right, and Geert Wilders stand together during a meeting of European Nationalists in Koblenz, Germany, on Saturday. (Michael Probst/Associated Press)

Wilders joined right-wing populist leaders from France, Germany, Italy and elsewhere on Saturday at a meeting in Germany ahead of elections this year that could see major gains for nationalist parties.

"I believe we are witnessing historic times," Wilders said, the day after U.S. President Donald Trump's inauguration.