A veteran Russian diplomat at the UN Office in Geneva says he tendered his resignation before drafting a scathing letter to foreign colleagues condemning Russian President Vladimir Putin's "aggressive war unleashed" in Ukraine.

Boris Bondarev, 41, acknowledged his resignation in a letter delivered Monday morning after a diplomatic official provided The Associated Press with his English-language statement.

About the day of Russia's invasion, he stated, "For twenty years of my diplomatic career, I have seen different turns of our foreign policy, but never have I been so ashamed of my country as on Feb. 24 of this year,"

The departure represents a rare — if not unprecedented — declaration of dissatisfaRussian diplomats' action with Russia's war in Ukraine by Russia at a time when Putin's regime has worked to suppress opposition to the invasion and narratives that contradict the Russian government's official account of how the "special military operation" — as it is officially termed in Russia — is progressing.

Bondarev wrote, referring to the widespread use of the letter, "The aggressive war unleashed by Putin against Ukraine, and in fact against the entire Western world, is not only a crime against the Ukrainian people but also, perhaps, the most serious crime against the people of Russia, with a bold letter Z crossing out all hopes and prospects for a prosperous and free society in our country," as a symbol of support for Russia's war in Ukraine, "Z."

Bondarev, a diplomatic counselor who has focused on Russia's position in the Conference on Disarmament in Geneva after postings in Cambodia and Mongolia, stated he sent his resignation letter to Ambassador Gennady Gatilov via telephone.

A mission spokesperson did not immediately reply to AP requests for comment.

"It is intolerable what my government is doing now," Bondarev told the AP. "As a public servant, I must bear some responsibility for this. And I do not wish to do so."

Bondarev stated that he had not yet gotten a response from Russian officials, but he continued: "Am I concerned about Moscow's prospective response? I must be concerned about it."

He informed the AP that he had no intention of leaving Geneva. Previously, he stated that he had voiced his opposition to the war to his Russian colleagues.

"Some said, 'Everybody disagrees, but we have to keep working' while others replied 'Shut up and stop spreading this bad influence– especially among younger diplomats,'" he recalled.

Bondarev, when asked if other colleagues shared his sentiments, responded: "Not all Russian diplomats advocate for war. They are sensible, but they must maintain silence."

He thought his situation could serve as an illustration.

"If my case is prosecuted, they would not," Bondarev stated if other people want to follow.

When asked if he intended to defect, he said with a smile, "I didn't think so far."

Bondarev said in his English-language statement, which he said he emailed to about 40 diplomats and others, that those who conceived the war "want only one thing — to remain in power forever, live in pompous tasteless palaces, sail on yachts comparable in tonnage and cost to the entire Russian Navy, enjoying unlimited power and complete impunity."

He railed against the growing "lies and unprofessionalism" at the Russian Foreign Ministry and singled out Foreign Minister Sergey Lavrov for specific criticism.

He wrote, "In 18 years, he (Lavrov) went from a professional and educated intellectual ... to a person who constantly broadcasts conflicting statements and threatens the world with nuclear weapons!" "The (Russian) Ministry of Foreign Affairs is no longer concerned in diplomacy. It is all about aggression, deceit, and hatred."

The executive director of UN Watch's advocacy organization, Hiller Neuer, tweeted a copy of Boris Bondarev's letter and stated, "Boris Bondarev is a hero."

"Bondarev should be invited to speak in Davos this week," he continued, referring to the annual meeting in Davos, Switzerland. "The US, the UK and the (European Union) should lead the free world in creating a program to encourage more Russian diplomats to follow and defect, by providing protection, financial security and resettlement for diplomats and their families."

Bondarev claimed in his email that he should have quit earlier but didn't due to "some unfinished family business" and the need to "gather my resolve."

It's already been three months since my government launched a murderous assault on Ukraine, and it's been tough to maintain my sanity while everyone around me was losing theirs, he wrote.