President Vladimir Putin's 61st birthday promised to be all work and no play with the president bound by "a schedule that leaves no room for celebrations," his spokesman Dmitry Peskov said.
But Putin's birthday on Monday did not escape the attention of his colleagues at the Asia-Pacific Economic Cooperation summit in Bali, Indonesia.
Indonesian President Susilo Bambang Yudhoyono surprised Putin and 19 other world leaders during lunch with a serenade for Russia's leader.
"I'm sorry, I hadn't realized that [Putin's] birthday was today," Yudhoyono said as the political leaders were getting ready to have lunch. "As soon as Mr. President [Putin] arrived I should have sung a song."
Yudhoyono then took to the stage and performed "Happy Birthday" on his guitar.
Putin was also handed a birthday cake by deputy chairman of the summit's organizing committee and given a bottle of sake by Japanese President Shinzo Abe.
"I thank President Yudhoyono for the birthday wish and it was a pleasant surprise," Putin said following the performance.
The Indonesian president is no stranger to the stage, having released three albums of love songs during his time in office.