Universal Children's Day (15 images)

UNICEF urged the world to help the 1 billion children still deprived of food, shelter, clean water or health care - and the hundreds of millions more threatened by violence - two decades after the U.N. adopted a treaty guaranteeing children's rights. On the eve of the anniversary, the U.N. children's agency issued a report Thursday on the challenges ahead and the accomplishments since the U.N. General Assembly adopted the Convention on the Rights of the Child in 1989.

UNICEF Executive Director Ann Veneman called a sharp decline in child deaths a "remarkable achievement," and lauded the increasing number of children attending primary school. More than 70 countries have used the treaty to incorporate children's rights in their national laws, she said, noting a new focus on safeguarding youngsters "from violence, abuse, discrimination and exploitation." Only two nations, the United States and Somalia, have not ratified it.

Read the story: UN urges help for 1 billion deprived children

A street child searches for recyclable material in a garbage dump on the outskirts of Gauhati, India, Thursday, Nov. 19, a day ahead of Universal Children's Day. (AP Photo/Anupam Nath)

Sheela, 6, walks the tightrope during a street performance in Gauhati, India, Wednesday, Nov. 18. (AP Photo/Anupam Nath)

Bangladeshi child laborers work at a balloon workshop in Kamrangir Char, on the outskirts of Dhaka on Thursday, Nov. 19. (AP Photo/Pavel Rahman)

Street children sleep on a pavement in Katmandu, Nepal, Friday, Nov. 20. (AP Photo/Gemunu Amarasinghe)

Children eat a meal at a shelter for street children in Katmandu, Nepal, Friday, Nov. 20. (AP Photo/Gemunu Amarasinghe)

In this photo taken Wednesday, Nov. 18, children wash clothes and bathe at a water pipeline surrounded by sewage in Mumbai, India. (AP Photo/Rafiq Maqbool)

A street child sleeps next to a stray dog as another looks for fleas in his clothes in Katmandu, Nepal on Thursday, Nov. 19. (AP Photo/Gemunu Amarasinghe)

In this photo taken Wednesday, Nov. 18, children look for recyclable materials at a garbage dump in Allahabad, in the northern Indian state of Uttar Pradesh. (AP Photo/Rajesh Kumar Singh)

In this photo taken Wednesday, Nov. 18, Roha, an infant, is left sleeping on the sidewalk of a busy street in Mumbai, India. (AP Photo/Rafiq Maqbool)

A street child displays acrobatic skills with the help of an iron ring during a street show in Katmandu, Nepal on Thursday, Nov. 19. (AP Photo/Gemunu Amarasinghe)

In this photo taken Wednesday, Nov. 18, a street child stands on a pile of garbage in Dharavi, Asia's largest slum, in Mumbai, India. (AP Photo/Rafiq Maqbool)

In this photo taken on Tuesday, Nov. 17, children rummage for scrap metal following a fire which gutted 400 houses in Mandaluyong city, east of Manila, Philippines. The Philippine Labor Department estimates that there are 2.1 million Filipino child workers, mostly in the agriculture sector. (AP Photo/Aaron Favila)

In this photo taken Sunday, Aug. 16, Marina, 3, center-left, plays with other children in the back of a garbage collection truck where many garbage collectors live and work on the outskirts of Cairo, Egypt. (AP Photo/Ben Curtis)

This Nov. 16 photo shows Palestinian teacher Gada Aby Ward teaching in the Omar Ben al-Khattab School. (AP Photo/Bernat Armangue)

This Nov. 17 photo shows a boy eating his lunch during recess at a school for children of migrant workers in a suburb of Beijing, China. (AP Photo/Elizabeth Dalziel)