MOSCOW (CNN) -- The Russian ambassador to the United Nations, Vitaly Ivanovich Churkin, died suddenly in New York on Monday the Russian Foreign Ministry said.

He died at age 64, one day before his 65th birthday.

"The outstanding Russian diplomat died while he was in his current working role," the Foreign Ministry said in a statement. "We offer our condolences to the relatives of Vitaly Ivanovich Churkin."

Matthew Rycroft, the British ambassador to the UN, called Churkin's deah the loss of a "diplomatic giant."

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