The Finnish mobile phone maker is providing substantial funds to help cover the cost of the concerts, of which there are now nine planned. Insiders at Nokia claim that it does not plan to use the events as a brand-building opportunity.
The sponsorship, which will be announced this week, is expected to be the first in a line of global deals to help fund the concerts, which will feature acts such as Coldplay and Madonna.
Organisers also contacted Coca-Cola about backing the London event, which will take place in Hyde Park, but it declined to take part.
A number of other brands are already heavily involved in the event. O2 ran this month's text lottery for tickets to the London concert, which attracted a record number of texts, while AOL is webcasting the concerts and Capital Radio is the official radio partner, having given up its use of Hyde Park for Party in the Park to Live 8.
John Kennedy of Live 8 said Nokia would "bring awareness and visibility to this important cause".
Nokia already has a number of music initiatives, including a headline sponsorship of the Isle of Wight music festival and its backing of this year's Prince's Trust Urban Music Festival.
It is using music to boost its popularity among the crucial youth market ahead of the UK launch of a range of music-enabled multimedia phones later this year.
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