Labaki, who won the prize on Saturday, is the first Arab woman to have won a major prize at the festival and only the second to have had a film competing for the Palme d'Or
Lebanese filmmaker Nadine Labaki, who won one of the top prizes at Cannes with a story of dirt poor children and migrants, dedicated her award to her impoverished amateur cast and her homeland.
Labaki, who won the prize on Saturday, is the first Arab woman to have won a major prize at the festival and only the second to have had a film competing for the Palme d'Or.
Her stirring film "Capernaum", whose 13-year-old Syrian refugee lead captured hearts in Cannes, had been tipped to win the Palme in a bumper years for films from North Africa and the Middle East.
Accepting the third-placed Jury Prize, Labaki said her thoughts were with a 12-year-old cast member, who she discovered selling tissues on the street, and who had probably again spent the day with "her face pressed against car windows".
"I really think about them (the cast). I hope the film will enable the voices of these children to be better heard and trigger a debate," she told reporters.
The glamorous 44-year-old added that she was "almost ashamed to be wearing such beautiful dresses" to promote her film about a boy who takes his parents to court for bringing him into a miserable, loveless existence.
"Capernaum", which won a 15-minute standing ovation at its premiere, catapults her into the big league after "Caramel", her intimate debut about a Beirut beauty parlour, and "Where Do We Go Now?", about women on a mission to end sectarian violence in their village.
In an interview with AFP this week she said that while she had previously amplified women's voices she "never really felt pressure to talk about women just because I am a woman."
"There are other things bothering me now," she said.
"I'm thinking of the notion of borders, of having to have papers to exist, of being completely excluded from the system if you do not have them, of the maltreatment of children, modern slavery, immigrant workers, and Syrian immigrants."
She does not spare the rod with her homeland in "Capernaum", at the risk of being accused by the Lebanese of washing their dirty laundry in public.
But as she triumphed at Cannes, Labaki was gracious with her country, "which, despite everything it is accused of, gets by as best it can," she said.
"It has welcomed the most refugees in the world (relative to its population), despite not having have the means to meet the needs of its own population."
But, she appealed: "We cannot continue to turn our back and remain blind to the suffering of these children who try their best to make their way in this capernaum (confused jumble) that the world has become."
Father's dream fulfilled
Labaki grew up during Lebanon's 1975-1990 civil war to a father who missed out on his dream of becoming a filmmaker.
"I said to my father, 'One day I will go to Cannes. So I have helped my father fulfil his dreams'," she said Saturday.
She came face-to-face with the idea for her feature when she was driving home from a party and saw a child half-asleep in the arms of his mother begging on the pavement.
"It became an obsession for me. I did more than three years of research. I was trying to understand how the system fails these kids."
Zain Al Rafeea, who has been working as a delivery boy in Beirut until recently -- and who has only just learned to write his name -- turns in a performance in "Capernaum" that had critics brushing away tears.
Being a mother helped Labaki craft some of the most moving scenes, featuring a gurgling breast-fed baby for which Zain has to fend after its migrant mother is arrested.
But she expressed reservations about the campaign for gender quotas in film casts and crews spearheaded by Hollywood actresses in the wake of the Harvey Weinstein scandal.
"It's not just because we decide that there should be parity in a given domain that it is truly merited. Whether it's a man or a woman it must be truly on merit," she told AFP.