Marine Le Pen, the leader of France's right-wing National Front (FN), was the first of Europe's populist and far-right leaders to call for an "immediate halt of all intake of migrants in France" on Monday.

Le Pen said in a statement that one of the terrorists responsible for the attacks in Paris on Friday had arrived in Greece last month "among the mass of migrants who flow into Europe each day."

"Islamic State" (IS) militants have claimed responsibility for the series of bombings and shootings in Paris on Friday, in which 129 people were killed and more than 350 were injured.

'Forget political correctness'

Hungarian Prime Minister Viktor Orban expressed similar views in Budapest's parliament on Monday, saying that the European Union had become "weak, uncertain and paralyzed" due to the migrant crisis.

The staunchly anti-immigrant leader, who has already blocked refugees from entering Hungary by erecting a barbed-wire fence, added that the EU's plan to relocate migrants among member states was unlawful and will "spread terrorism around Europe."

"We don't think that everyone is a terrorist, but no one can say how many terrorists have arrived already, how many are coming day by day," Orban said, adding that the EU needs to "forget political correctness ... and return to common sense."

'Attacks didn't come out of nowhere': PEGIDA

In Germany, right-wing movement PEGIDA (Patriotic Europeans Against the Islamization of the West) also carried out their usual Monday demonstration in Dresden.

A leader of the self-styled movement, Siegfried Däbritz, told the 10,000-strong crowd that the Paris attacks were "the result of an immigration policy that invites people from completely foreign cultures with completely different values into countries and regions, whose culture many of these immigrants despise."

Beyond Europe, governors in more than a dozen US states have also threatened to stop efforts to take in Syrian refugees.

"I will not stand complicit to a policy that places the citizens of Alabama in harm's way," said Republican Governor Robert Bentley.

According to immigration experts, however, governors would be unable to legally block refugees from settling in their states under the Refugee Act of 1980.

'Mistake of equating refugees with terrorists'

The United Nations hit back at the calls to refuse entry to refugees on Monday, saying that "the reaction to the wave of refugees we have seen should be one of compassion and empathy."

"It is understandable that countries need to take whatever measures they need to take to protect their own citizens against any forms of terrorism," said UN spokesman Stephane Dujarric.

"But focusing that on refugees, vulnerable people who are themselves fleeing violence, would not be the right way to go," he said.

Officials in Germany also urged the public on Monday to not demonize the wave of refugees arriving from crisis areas in Africa and the Middle East.

"We must not make the mistake of equating refugees with terrorists," Defense Minister Ursula von der Leyen told the Monday edition of the German newspaper "Passauer Neuen Presse."

"The hundreds of thousands of men, women and children have left their homeland to escape exactly the type of atrocities that we have seen in Paris on Friday," she said.

ksb/cmk (AFP, AP, dpa)