They may not be fans of his music - and they almost certainly didn't get his jokes - but that didn't stop a hall of sober-suited technocrats enthusiastically applauding Bono yesterday following an impassioned speech on Africa's future.
Swapping his crumpled safari shirt for a suit and tie, the Irish singer outlined his agenda for reviving the continent before the annual meeting of the African Development Bank (ADB) in the Ethiopia capital Addis Ababa.
Africa's indebtedness to the west was "insanity", he said, certain development policies were "the new colonialism" and billions of dollars in extra aid were urgently needed.
"Africa, this is your century," he said. "Let's not wait until the end of the century."
As he left the hall, delegates scrambled for autographs and photographs with the pop star turned third-world campaigner.
The singer came towards the end of a 10-day tour of Africa with Mr Paul O'Neill, the US Treasury Secretary, in what has become a rolling debate on how western aid should be spent.
Sharp differences have sometimes emerged between the unlikely pair, with the Dubliner's emotional appeals contrasting with the "results-oriented" approach of the multi-millionaire conservative politician.
Yesterday Bono joked that Mr O'Neill, who will report back to President Bush after the trip ends tomorrow, was "a man who would ask God for measurable results."
" But he was "not just a suit and tie", he said. "He has a heart and a head for these problems. In my opinion he is the right man for the job. He is God's messenger."
Ethiopia has a special significance for Bono, who helped Bob Geldof raise $200 million to combat famine in the 1980s. The U2 frontman spent six weeks in a feeding camp with his wife Ali.
"We thought we'd cracked it; it was a great moment," he said of the Band Aid and Live Aid fundraising. But then he discovered that African countries were paying the same sum of money every five days in debt repayments.
"This is not acceptable to us on any level, anyhow, anywhere," he said.
Since his Africa tour started 10 days earlier, over 55,000 people had died of AIDS and their governments had spent $400 million on debt repayments, he said."I can't believe that. It's insanity."
The structural adjustment policies of the International Monetary Fund and World Bank were "the new colonialism", the musician warned.
Yet the also challenged African leaders to become more democratic, singling out the Ethiopian Prime Minister, Mr Meles Zenawi.
Earlier in the day, aid agencies met Bono to complain about the government's strict controls on their activities. Ethiopia is one of the six priority beneficiaries of Irish Government aid.
Bono also visited a coffee plant with Mr O'Neill. Coffee should be Ethiopia's key export but prices have plummeted in recent years. Mr O'Neill hailed the factory owner as "the sort of entrepreneur that makes the world work".
But Bono said he felt "uneasy" about seeing factory workers who earned $1 a day, even if it was four times the average wage.