As many as 200,000 people -- many wearing white -- have formed a human chain around Scotland's medieval capital of Edinburgh, pressing for action against African poverty at next week's Group of Eight summit at the nearby Gleneagles resort.
The good-natured crowd waved banners, blew whistles and carried white balloons, the symbolic color of the anti-poverty campaign.
Saturday's "Make Poverty History" march coincides with Live 8 rock concerts being held around the world.
In a message read to the demonstrators, Pope Benedict urged wealthy nations to make good on pledges to reduce world poverty. He said God intends the world's resources to be available to all.
The demonstrators want industrial nations to cancel African debt, increase aid to poor nations and remove trade barriers blocking the import of African products.
Leaders of the world's seven principal industrial countries: Britain, Canada, France, Germany, Italy, Japan and the United States and Russia begin their summit Wednesday.