The lives of millions of Yemeni children are at "high risk" as the country moves closer to famine, UNICEF warned on Monday.

“Chronic poverty, decades of underdevelopment, and over five years of unrelenting conflict have exposed children and their families to a deadly combination of violence and disease," Executive Director Henrietta H. Fore said in a statement.

Yemen has been beset by violence since 2014, when Iran-backed Houthi rebels overran much of the country, including the capital Sanaa.

The crisis escalated in 2015 when a Saudi-led military coalition launched a devastating air campaign aimed at rolling back Houthi territorial gains.

Thousands of people have been killed in the conflict, which is seen as a proxy war between Saudi Arabia and Iran.

Fore said more than 12 million Yemeni children need humanitarian assistance, nearly 325,000 children under the age of five suffer from severe acute malnutrition, while more than five million children face a heightened threat of cholera and diarrhea.

She added that the COVID-19 pandemic has turned a "deep crisis" into an "imminent catastrophe."

The official appealed to address an urgent funding gap of $300 million, as well as to end the years-long war.

“Children in Yemen need peace. An end to this brutal conflict is the only way they can fulfil their potential, resume their childhood and, ultimately, rebuild their country,” Fore said.