File photo taken on June 30, 2012 shows then UN and Arab League Envoy to Syria Kofi Annan during a press conference in Geneva, Switzerland. (Xinhua/Xie Haining)

MOSCOW, Aug. 18 (Xinhua) -- Russian President Vladimir Putin on Saturday sent a message to United Nations (UN) Secretary-General Antonio Guterres, expressing his deepest condolences over the death of former UN chief Kofi Annan.

"This remarkable man and great politician dedicated many years of his life to serving the United Nations," Putin said in the message published on the website of the Kremlin.

Annan served at the helm of the United Nations during a complicated period and did a great deal to achieve the goals and tasks of the organization, enhancing its central role in global affairs, Putin said.

"Especially significant was his personal contribution to building up the peacemaking potential of the UN and settling a number of regional conflicts ... The memory of Kofi Annan will remain in the hearts of Russians forever," he said.

Russian Foreign Minister Sergei Lavrov also sent a message of condolences to Guterres on Annan's death.

Annan, who was also a Nobel Peace laureate, passed away earlier in the day in a Swiss hospital at the age of 80.