Soccerex, a major football convention scheduled to take place in Rio de Janeiro in late November, was cancelled, reportedly because of safety fears.

It comes after the 2013 FIFA Confederations Cup in June was marred by protests, with fears there will be a repeat at the World Cup next year.

Ronaldo, 37, is a member of the organising committee and said he understood why the country's people were protesting.

"I'm fighting for something that we are building. It is very easy for someone to be the opposition, trying to destroy from your house without believing in a project, not believing in anything and just trying to destroy it," Ronaldo said.

"I am not doing it for myself. I am a volunteer for the World Cup, I am not earning any cents from the committee or FIFA. I am doing it because I believe in my country and in my people.

"And I believe this is a great thing for our country, a great growth opportunity for our country. So I'll keep acting the same way, believing in my country, believing in the Brazilian people and I really hope to have an improvement in living conditions.

"I agree with all types of protest without violence, the Brazilians are so tired of the neglect that had for many years and now we are waiting for answer by government. I am doing my part, which is to have a Brazil better even if it is through sports."

Former English sports minister Richard Caborn said the protests seen at the Confederations Cup were a worry for the World Cup.

"It must be a concern. It must be a concern clearly for those in the organisation down in Brazil," he said.

"I don't know what happened with Soccerex, like you, I just read the press notices which came out this morning.

"Clearly if it is in that same vein that you saw around the Confederations Cup then there is real concern about the unrest there, then obviously that doesn't bode well.

"I'm sure that they will be putting things in place hopefully that will start at least mitigating against those circumstances."