United Nations Secretary General Ban Ki-moon will not attend the opening ceremony of Beijing [Images] Olympics [Images] but his absence was not linked to the Tibetan protests.

Ban's spokesperson Marie Okabe said on Thursday that the UN chief would not be able to make it to Beijing in August due to 'scheduling problems'.

Ban had been invited by China but the Secretary-General "conveyed to the Chinese government some months ago that he may not be in a position to attend this important event as a result of scheduling issues", Okabe said.

Several human rights and activist groups have urged the world leaders not to participate in the ceremony to protest against repression in Tibet [Images] and failure of the Chinese government to pressure its close ally Sudan to end the genocide in Darfur.

British Prime Minister Gordon Brown has already announced that he will not attend the ceremony while US President George W Bush [Images] is under intense pressure to boycott the Games.