Jaroslaw Kaczynski's comment in the Gazeta Polska weekly that was published Wednesday suggest that his party's wariness toward Russia could be an impediment to working with Le Pen's National Rally or the right-wing League party of Italian Interior Minister Matteo Salvini, who is also friendly toward Russia.
Salvini has positioned himself at the forefront of a growing movement of nationalist leaders seeking to free the EU's 28 nations from what he called Brussels' "illegal occupation."
He gathered nationalists, including Le Pen, from across Europe in Milan on Saturday seeking unity ahead of this weekend's elections to the European Parliament.
Salvini also visited Warsaw earlier this year seeking to woo Law and Justice to his grouping, but found limits to cooperation due to Poland's bitter memories of occupation and control by Moscow over centuries.
"I see political formations operating in individual countries that are obviously linked to Moscow and receive its support. Mrs. Le Pen's formation is a good example of this," said Kaczynski, the leader of Law and Justice and the key figure directing government policy and appointments.
"So the most important question is: how far the policy of such formations would be influenced by the Kremlin if they became a key force in the EU? In other words, how strong are these ties and dependencies?" Kaczynski said.
Le Pen's party, formerly called the National Front, took millions of euros in loans from a Czech-Russian bank.
Russian President Vladimir Putin also hosted her at the Kremlin in 2017 during the French presidential campaign, part of his larger embrace of nationalist and anti-globalist forces in the West.
But earlier this month during a visit to Estonia, Le Pen sought to play down her association with Putin: "I'm not under the control of any foreign country" and that "I will not allow for us to be under Putin's thumb."
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