K'naan travelled to 80 countries this year as part of a World Cup promotional tour. The performer says he's tired, unhappy over a breakup and feels the urge to write new songs. (Handout/Canadian Press)

Canadian hip-hop sensation K'naan, whose song Wavin' Flag was chosen as Coca-Cola's World Cup anthem and has also been used to help raise money for Haiti's earthquake victims, has taken to Twitter to apologize for a lacklustre concert in Ireland.

"In all my years of touring, today marks the 1st time I've played an entire concert w/out feeling a thing. Just going through the motions," he tweeted early Saturday afternoon.

"I don't wanna be like this. Like 1 of those artists."

The Somali-born, Toronto-based musician had just played Stradbally, Ireland at the Electric Picnic Festival and he's set to perform Monday in London before kicking off a month-long tour in Canada.

K'naan's personal story has touched thousands of people. As a child, he saw his friends killed during Somalia's brutal civil war. When he reached relative safety in Canada as a teenager, he still experienced the tragedies of watching friends die on the streets of Toronto.

The 32-year-old performer divulged his emotional state, partly blaming his exhausting touring schedule in the run-up to the World Cup in South Africa in June.

"It could B b/c I've done over 80 countries this year, could B spiritual & physical fatigue, it could B that I need 2 get out new songs … It could be since my breakup a year and a half ago that I haven't had a significant or lasting relationship. I can't say what it is," he revealed.

"All I know is, I feel sickly ever having to play these songs of personal redemption with an insincere stage presence.

"I reach U through all the noise b/c my heart is in my songs. I never wanna lose that," the Juno winner concluded.

He finished off the tweet by thanking his 44,000 followers and fans: "I don't know what 2 do about all this but thank U so much 4 reading."