GENEVA: Hundreds of thousands of children in Yemen face life-threatening malnutrition and millions lack access to health care or clean water due to the year-old war there, the UN Children's Fund said on Tuesday.

A UNICEF report also said all sides in the war had "exponentially increased" the dragooning of child soldiers, with 848 documented cases - including boys as young as 10 - forced to fight.

Tensions appear to be easing between the Iran-allied Houthis, who control most of northern Yemen, and Saudi-led forces after a year of war, over 6,200 deaths and a humanitarian crisis in the Arab world's poorest country.

"On average, at least six children have been killed or injured every day," said the report "Childhood on the Brink". UNICEF has confirmed 934 children directly killed and 1,356 injured, but says they are "only a tip of the iceberg".

Devastating lives - 934 children were killed and 1056 were injured in #Yemen in the last year, @julienmh tells journalists at UN Geneva.

— UN Geneva (@UNGeneva) March 29, 2016

"Basic services and infrastructure in Yemen are on the verge of total collapse," it said, noting attacks on schools, hospitals and the water and sanitation system.

The United Nations said last week the warring parties had agreed to a cessation of hostilities from April 10 and peace talks from April 18.

"We're hoping that the truce kicks in on the 10th and will allow parents and families to come and access health services and other services," Julien Harneis, UNICEF's Representative in Yemen, told Reuters by telephone from Sana'a.

"In Sa'ada in the last week, there has definitely been a reduction of fighting in the border area. In Sana'a, we have seen fewer (Saudi-led) air strikes," he said.

Nearly half of Yemen's 22 provinces on the verge of famine and over 13 million people need food aid, the UN's World Food Programme said last week.

UNICEF delivers nutritional supplies and vaccines against measles, polio and other childhood diseases in the country of 24 million, but it is not enough, Harneis said.

"We've got an increase in both severe acute malnutrition and chronic malnutrition," he said.

The report said an estimated 320,000 children risk severe acute malnutrition, which can leave a child vulnerable to deadly respiratory infections, pneumonia and water-borne diseases.

Nearly 10 million children require humanitarian aid to prevent a further deterioration. Chronic malnutrition can stunt growth and development.

"UNICEF estimates that nearly 10,000 children under 5 years may have died in the past year from preventable diseases," it said, citing lower vaccination rates and declines in treatment.