Hip-hop star Kanye West is still feeling the pain over his ambush of Taylor Swift last year - and he's expressing it on Twitter.

West unleashed a torrent of emotions on his official Twitter account on Saturday. He acknowledged once again that he was wrong for jumping on stage, grabbing the microphone from Swift at the MTV Video Music Awards and saying her trophy should have gone to Beyonce.

"How deep is the scar ... I bled hard ... cancelled tour with the number one pop star in the world ... closed the doors of my clothing office," he tweeted.

When the multi-platinum, Grammy-winning superstar upstaged Swift - the then-teenage darling of pop and country music worlds - the public had had enough. Even President Barack Obama was caught calling him a "jackass".

After the incident, he said, "People tweeted that they wish I was dead ... They wanted me to die. I carry that. I smile and take pictures through that."

West said he's now "ready to get out of my own way. The ego is overdone."

He also apologised to Swift again, and said he has written a song for her that he hopes she will perform.