New York, June 14 (Agencies): At least 400 million people lack access to essential health services, the World Health Organization and World Bank said Friday in a new report that they described as a "wake-up call" about the challenges to achieving universal health coverage.

The report also said that at least 6 per cent of people in 37 low-and-middle-income countries are living in poverty because of the money they must spend on health. That finding alone suggested that the poorest could be left further behind by rising global health costs.

"The world's most disadvantaged people are missing out on even the most basic services," Marie-Paule Kieny, assistant director-general for health systems and innovation at the WHO, said in a statement announcing the98-page report, which was released online and at a news conference at United Nations headquarters in New York.

Timothy G Evans, senior director of health, nutrition and population at the World Bank Group, said the report's findings illustrated the vulnerability of the world's poorest people to health expenses.

"This report is a wake-up call," he said. "It shows that we're a long way from achieving universal health coverage."

While the findings in the report, "Tracking Universal Health Coverage," were not surprising, its creators said they had nonetheless established benchmarks for measuring both health coverage and financial protection from the cost. They said the findings would help assess whether United Nations member states were advancing the aspiration of universal health coverage.

"As the saying goes, 'what gets measured, gets done,'" said Michael Myers, managing director at The Rockefeller Foundation, which helped support the work in creating the report.

The findings could also help measure progress in the proposed Sustainable Development Goals, part of a broader agenda undertaken at the United Nations. The 17 goals include ending poverty and hunger and ensuring healthy lives and well-being for all ages.

Universal health coverage was broadly defined in the report as "all people receiving the quality health services they need, without being exposed to financial hardship".

The report examined access around the world to health services considered essential, including family planning, prenatal care, skilled birth attendance, child immunisation, antiretroviral therapy to combat HIV and AIDS, tuberculosis treatment and access to clean water and sanitation. The findings showed that 400 million people lacked access to at least one of these services.

In assessing how much consumers of health care must pay, the report found that in low-and-middle income countries, 6 percent of the population had been reduced to poverty - defined as living on $1.25 a day - because of out-of-pocket health expenses. If poverty was defined as living on $2 a day, the portion of the population in this category because of health expenses rose to 17 percent, the report found.

"These high levels of impoverishment, which happen when poor people have to pay out-of-pocket for their own emergency health care, pose a major threat to the goal of eliminating extreme poverty," said Kaushik Basu, the World Bank Group's chief economist.