Up to 50,000 demonstrators are expected to march through the Swiss border city of Geneva to protest against capitalism, exploitation and a range of other issues ahead of the G7 summit in the French town of Évian.
The protest on Sunday is being organised by a No G7 coalition of several dozen groups.
The demonstration is taking place in Geneva because France declined to issue permits for any protests near the G7 summit venue, the Geneva city government said, criticising the decision.