Apple boss Steve Jobs to be replaced by Tim Cook

Mr Jobs, who underwent a liver transplant following pancreatic cancer, said he could no longer meet his chief executive's duties and expectations.

The Silicon Valley legend will become chairman of the firm.

The 55-year-old has been on medical leave for an undisclosed condition since 17 January.

In a short letter to the board of Apple, Mr Jobs wrote: "I have always said if there ever came a day when I could no longer meet my duties and expectations as Apple's chief executive, I would be the first to let you know.

"Unfortunately, that day has come. I hereby resign as chief executive of Apple.

"I believe Apple's brightest and most innovative days are ahead of it. And I look forward to watching and contributing to its success in a new role.

"I have made some of the best friends of my life at Apple, and I thank you all for the many years of being able to work alongside you."

Apple board member Art Levinson paid tribute to Mr Job's contribution to the company: "Steve's extraordinary vision and leadership saved Apple and guided it to its position the world's most innovative and valuable technology company;" Kazinform cites BBC.

To learn more go to www.bbc.co.uk