Live 8 leader Bob Geldof has arrived in Edinburgh by train ahead of Wednesday's Final Push gig, saying he is confident of a "breakthrough" at the G8 summit.
Geldof talks to the media outside Edinburgh's Waverley Station
He condemned the protesters who were involved in battles with police on Monday as "a bunch of losers".
Geldof denied undermining Saturday's Make Poverty History march in the city by scheduling the worldwide Live 8 concerts for the same day.
He said that two campaigns had the same message - to end third world suffering.
The former rock star was joined by Hollywood acting couple Tim Robbins and Susan Sarandon on the special Virgin train to Edinburgh from London's Euston station with campaigners from Make Poverty History.
He said: "We hope to achieve a historic breakthrough. This is a very different G8 this time, I have been to a lot of G8s and this one is substantively different.
"The negotiators have been taken from the table. The British Government will not lower the bar to the lowest common denominator."
Geldof said he believed it was important to keep the pressure on world leaders because for this G8 summit deals were not being done in advance and important decisions could still be taken.
Geldof had called for a million people to attend the Long Walk to Justice rally on Wednesday.
Although it was unclear how many people had descended on Edinburgh, reports suggested this figure was unlikely.
Edinburgh Council set up a campsite with a capacity of 15,000, specifically for people arriving for the G8 rallies.
By Tuesday afternoon, just under 1,000 people were at the campsite in the Craigmillar area of the city, the council said.
Virgin Trains spokesman David Ewart said the number of people travelling to Edinburgh had definitely increased since Friday, and cross country trains had been fitted with extra carriages.
"Seat reservations have been heavy for many trains," he said.
A spokeswoman for VisitScotland.com said accommodation inquiries for Edinburgh "saw a surge" on Monday, with bookings up by 20% from last year.
But she added, there was still "widespread availability". Edinburgh's tourist accommodation was set to be around 60% full during the G8 summit.
Malcolm Fleming, a Make Poverty History and Oxfam Scotland spokesman, said numbers at Saturday's Make Poverty History march had been "two and half times" more than expected and the mood was still positive.
"My understanding is that the 'million' call was always a symbolic one," he said.
"There are people here from Africa, Asia and Latin America who are campaigning against poverty in their own countries," he said.
"They have responded to the Global Call for action against poverty and they represent hundreds of thousands of people."
He added there were also people from Japan, France and the US who hoped to lobby their own leaders who were attending the summit.
Hollywood couple Tim Robbins and Susan Sarandon with Bob Geldof
Geldof said he believed the Live 8 concerts had made a difference.
"Look at George Bush's reaction where he said he watched the concert all day and it was a great piece of mass advocacy," he said.
"After the concert he began talking about trade. He started talking in very different language.
"This is an interesting political match taking place at the G8, this is the first time this summit is serious."
He added that Monday's clashes between anarchists and police in Edinburgh ahead of the G8 summit were a "side issue" compared with the "extreme violence" of third world suffering.
Geldof called the violent protesters "idiots" who thought they were going to create world revolution by standing on top of park benches and hitting policemen".
Geldof said it was "unacceptable" for politicians such as Chancellor Gordon Brown to warn that campaigners may be disappointed by the outcome of the meeting of the world's richest nations.
He said; "I'm not prepared to be disappointed. I don't think that is an option."
Geldof is in Scotland as part of the Long Walk to Justice campaign which will culminate with a 60,000-strong concert at Murrayfield.