He was to address a gathering organised by followers of Turkey's most powerful Sunni cleric, Fetullah Gulen, who has long preached friendship between Turks and Iraqi Kurds.

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In a frank 13-minute address to a select gathering at PGA Tour headquarters in Florida, Woods apologised to his wife, friends and family as well as his fans.

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On Friday, First Minister Jack McConnell will address the gathering in a keynote speech.

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He was also forced to abandon plans to address the gathering by a video link after protesters threatened to march on the venue.

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Bachelet, Brown, Lula da Silva and Stoltenberg will address the gathering Friday night to speak about charting a progressive path in response to the global economic crisis.

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Jackson delivered a keynote address at the National Council of Churches Centennial Gathering in New Orleans.

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Bono is the latest in a string of high-profile speakers from around the world to address the annual gathering in recent years, following on from Nelson Mandela, Bill Clinton and Afghanistan president Hamid Karzai.

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