The Kremlin wants Russian lawmakers to refrain from inviting high-level foreign guests to Victory Day commemorations next spring, the Open Media news website reported Monday.

President Vladimir Putin has invited several foreign leaders, including U.S. President Donald Trump and French President Emmanuel Macron, to attend Russia’s parade marking the end of World War II on May 9. Trump’s response that he would consider traveling to Moscow for the 75th anniversary of the Soviet forces’ defeat of Nazi Germany has sparked an outcry among U.S. commentators.

The Kremlin has asked State Duma speaker Vyacheslav Volodin to discourage lawmakers from meeting with high-level foreign contacts on May 7-10 unless specifically cleared with the Kremlin, Open Media reported.

According to the outlet, instructions for seeking Kremlin clearance were laid out in a letter penned by Putin’s adviser and senior Victory Day organizing committee member Anton Kobyakov.

The purpose of Kobyakov’s letter is “so that there’s no independent activity during the holidays,” an unnamed member of the ruling United Russia party was quoted as saying.

Another unnamed person familiar with the Victory Day preparations told Open Media that Putin’s administration wants to prevent “undesirable persons” from entering Russia during what Moscow expects to be a major celebration. The source did not provide examples of who an undesirable guest might be.

Kobyakov’s reported letter bears similarities to a government order earlier this year for Russian scientists to avoid communicating with their foreign colleagues unless formally authorized to do so. The Kremlin said at the time that Russia needed to remain vigilant in the face of foreign espionage.

Putin said last week it would be the “right” thing for Trump to attend the commemorative event in Moscow, even as the U.S. president campaigns for re-election.

Trump has said he was considering attending the commemorative events after receiving an invitation from the Kremlin.

Reuters contributed reporting to this article.