Despite recent declines in the incidence of child labor much more must be done to tackle the issue, the Third International Conference on Child Labor heard Tuesday.
International Labor Organization (ILO) Director-General Guy Ryder urged redoubled efforts, decrying the fact a target to eliminate the worst instances of child labor by 2016 will not be met.
Latest ILO global estimates show the total number of child laborers has dropped by one-third to 168 million since the last conference in The Hague in 2010.
But Ryder said that still is nowhere near good enough.
"Let us be clear. We will not meet the 2016 target and that is a collective policy failure. We have to do better," Ryder told delegates.
"These children constitute 168 million reasons for our presence here today," Ryder added.
"The call from #Brasilia must be for a renewed and collective effort. Please make that call," he also tweeted.
Ryder opened the conference alongside Brazilian President, Dilma Rousseff, who said that "we owe all children a future without violence, without fear and without exploitation."
Conference spokeswoman Paula Montagner told AFP governments had to unite to have a hope of eradicating the problem.
"We have to increase the rhythm of this reduction (since 2010) and consider that the sharing of experience between governments will enable us to defeat this evil," Montagner said.
Representatives from 193 countries have gathered this week in the Brazilian capital Brasilia to draw up a plan of action, noting that children account for 30 percent of domestic workers globally.
The conference is committed to the eradication of the worst forms of child abuses in the workplace -- targeting sexual exploitation, human trafficking, drug trafficking and also exposure of underage laborers to noxious substances.
A further commitment is to highlight the plight of children working in difficult-to-monitor sectors of the economy, such as agriculture and the black economy.
Montagner says the goal is to eliminate exploitation and ensure minors concerned gain access to quality education.
A further goal is to aid refugees and child migrants who, along with their families, often experience difficulty in accessing services as they have no citizenship rights in the country where they end up.
"We must dispense with the idea that adolescents can work in production processes," said Montagner, calling for social policies which helped families and which would not compromise their children's future.