(CNN) Russia has filed a complaint with the United Nations over comments by a top UN official condemning Donald Trump and right-wing European politicians, two diplomats knowledgeable about the matter told CNN.

The officials said Russian UN Ambassador Vitaly Churkin complained in a meeting with UN Secretary General Ban Ki-moon last month about a pair of speeches by Zeid Ra'ad al-Hussein, the UN High Commissioner for Human Rights.

"He should stick to human rights," Churkin said of Zeid. "He should not be criticizing foreign heads of state and governments for their policies. This is not his business. He should be more focused on his specific responsibilities."

In an April speech at Case Western Reserve University's law school in Cleveland, three months before Republicans held their convention in the city nominating Trump, Zeid said "a front-running candidate to be president of this country declared, just a few months ago, his enthusiastic support for torture," a reference to remarks by Trump in which he pledged to restore waterboarding and even harsher interrogation methods for suspected terrorists.

While he didn't mention Trump by name, Zeid said the candidate was engaged in "a full-frontal attack -- disguised as courageous taboo-busting -- on some fundamental, hard-won tenets of decency and social cohesion."

Zeid noted he was a Muslim who had studied in the United States and has spent many years living in what he called a country "embodied by its bonds of inclusion, the freedom to be yourself, represented well and served fully by a government transparent and accountable for all its citizens' individual rights."

The Russian protest fuels questions about links between Trump's campaign and the Kremlin, after US intelligence agencies publicly blamed Russia for recent hacks into the Democratic National Committee and other Democratic-affiliated groups, which if true would be a stunning display of a foreign power's meddling in a presidential election.

Democratic nominee Hillary Clinton has sought to make Trump's glowing comments about Russian President Vladimir Putin and Russia-friendly foreign policy platforms an issue in the 2016 election. Her campaign has also raised concerns about connections between Moscow and members of Trump's campaign, arguing that if the Republican nominee is elected, he would be someone Putin could manipulate.

"This is not only strange -- it's scary," Jake Sullivan, Clinton's primary foreign policy adviser, said of the Russian complaint to the UN. "A major party candidate for the presidency of the United States is being protected by the Kremlin. Wow."

Hope Hicks, Trump's campaign spokeswoman, told CNN the campaign was not aware of Zeid's remarks or Russia's protest.

In a second speech last month at the Hague, Zeid, the former Jordanian ambassador to the US, lumped Trump with several populist European politicians whom he blasted as "demagogues and political fantasists," including Nigel Farage, a leader of Britain's pro-Brexit campaign, French nationalist leader Marine Le Pen and Dutch Nationalist leader Geert Wilders, who received the lion's share of his criticism. In August, Wilders' Freedom Party promised a platform calling to close mosques and Islamic schools and ban the Koran if it won the Netherlands' election next March.

Zeid also singled out other politicians who have taken anti-Muslim, anti-migrant and pro-Russian stances, including Slovakian Prime Minister Robert Fico, Hungarian Prime Minister Viktor Orban, Czech President Milos Zeman and Austrian presidential candidate Norbert Hofer.

"All seek in varying degrees to recover a past, halcyon and so pure in form, where sunlit fields are settled by peoples united by ethnicity or religion," Zeid said, adding that he believed the politicians had similar sentiments to ISIS.

Churkin told reporters Monday he had not seen Zeid's remarks and that he delivered the protest to the UN upon instructions from Moscow in one of his regular meetings with Ban. He said he also raised the issue with Zeid.

Churkin said he did not not bring up Trump in his protest.

"If it were Trump (who Zeid was referring to in his speeches), then the United States should have complained because it would have meant that he is interfering in their domestic presidential campaign," he said. "But I am not working for the United States. I am working for the Russian Federation, so why should I complain when somebody is trying to interfere with the US presidential campaign?"

However, the UN diplomats said Churkin specifically complained to Ban about Zeid's mention of Trump and other politicians. The diplomats spoke on the condition of anonymity to avoid appearing to criticize Russia, a permanent member of the UN Security Council.