More than two billion people worldwide still lack access to safely managed drinking water, the United Nations said, warning that progress towards universal coverage was moving nowhere near quickly enough.

The UN's health and children's agencies said in a report published on Monday that a full one in four people globally lacked access to safely managed drinking water last year, with over 100 million people remaining reliant on drinking surface water, such as from rivers, ponds, and canals.

The World Health Organization and UNICEF said lagging water, sanitation and hygiene (WASH) services were leaving billions at greater risk of disease.

They said in a joint study that the world remains far off track to reach the target of achieving universal coverage of such services by 2030.

Goals slipping from reach

Instead, that goal "is increasingly out of reach," they warned.

"Water, sanitation and hygiene are not privileges: they are basic human rights," said the WHO's environment chief, Ruediger Krech.

"We must accelerate action, especially for the most marginalised communities."

As for sanitation, 1.2 billion people have gained access to safely managed sanitation services since 2015, with coverage rising from 48 percent to 58 percent, the study found.

These are defined as improved facilities that are not shared with other households, and where excreta are safely disposed of in situ or removed and treated off-site.

The number of people practising open defecation has decreased by 429 million to 354 million in 2024, or to four percent of the global population.

Since 2015, 1.6 billion people have gained access to basic hygiene services, a handwashing facility with soap and water at home, with coverage increasing from 66 percent to 80 percent, the study found.