Live 8 (search) organizer Bob Geldof (search) on Tuesday condemned the G-8 protest violence in Scotland's capital and said it would be "grotesquely irresponsible" for world leaders at the summit to renege on promises of aid for Africa.

Geldof, a former rock star who has led anti-poverty efforts, has called for 1 million people to take part in a "Long Walk to Justice" on Wednesday to pressure Group of Eight leaders meeting this week in nearby Gleneagles.

Hundreds of black-clad anarchists and other protesters fought with police in Edinburgh on Monday, leaving 20 police and demonstrators slightly injured. About 100 people were arrested and to appear in court Tuesday.

The clash "was just stupid and unnecessary and to be condemned," Geldof said. "We should look at what happens in Africa and what happens to the poor, the extreme violence visited upon them by poverty."

Protests continued throughout Scotland on Tuesday.

Three campaigners from the World Development Movement climbed a crane towering over Edinburgh's Waverley railway station and unveiled a banner declaring "No more brownwash" — suggesting that British Treasury chief Gordon Brown isn't serious in his efforts to help African nations.

Brown, who has pushed for debt relief, free trade and a doubling of international aid to Africa, said Tuesday that supporting the continent is the "greatest moral crusade of our time." But he also warned that the G-8 (search) is unlikely to meet the expectations of anti-poverty campaigners.

"I know that ... you will tell us we've got to do more. I know that what you will say is that what we can achieve is perhaps not good enough," Brown told the British Broadcasting Corp. "But we have got to bring the whole of the world together. What Britain says is one thing; what we can persuade the rest of the world to do together is what we will get as the outcome of Gleneagles."

Geldof, who left London by train with representatives from protest campaigns in France, Georgia, Ghana, Mali, Sierra Leone and Britain, said he was "not prepared to be disappointed." He insisted the British government should not stop pressing for what the G-8 should achieve.

"I don't think that is an option. I don't think the chancellor should try lowering the bar at this stage," Geldof said. "We have come for victory. It has to happen now. Not to do it now would be grotesquely irresponsible. It is unacceptable for politicians to say 'prepare to be disappointed.'"

Rock stars, including Annie Lennox and the band Texas, will take part in a concert Wednesday called "Edinburgh 50,000: The Final Push." Organizers say the figure refers to the number of people who will die that day alone from extreme poverty.

Blair's Commission for Africa report calls for debt relief, fair trade, an extra $25 billion a year in international aid for the continent by 2010 and a further $25 billion annually up to 2015.

The report also calls on Africans to improve governance, resolve conflicts and stamp out corruption.

In Auchterarder, the village closest to the Gleneagles resort where the world leaders will gather, Chief Constable John Vine of the Tayside police said officers would be firm against any protest violence.

"We want to allow the peaceful protest of the majority to take place unhindered by any rogue elements who are set on disruption and confrontation," he said. "We will not flinch where we encounter such behavior and will deal with it in a robust and measured way."

Britain, which is chairing the G-8 summit this year, has already secured agreement to wipe the debts of 18 of the world's poorest countries, on the condition that certain democratic and economic benchmarks are met.

"Their plans for debt relief and aid are attached to stringent conditions, and there is no mention of the urgent need for trade justice," said anti-poverty campaigner Paul Hutchings, who traveled from Brighton on England's southern coast for G-8 protests.

Environmental activists also planned to demonstrate later Tuesday at an oil refinery in Grangemouth, about 20 miles west of Edinburgh.