Doctors without Borders (MSF) says risk-aversion and bureaucracy are increasingly preventing international aid agencies from helping the world’s most desperate people in emergency situations.

The statement was made by the Swiss-based medical charity in a report published on Monday.

In its analysis of recent major emergencies, the MSF said that inflexibility was leading to “atrophy of the humanitarian system” despite greater funding and expertise.

“Humanitarian responses are slow and cumbersome, and lack impact... Many agencies are concentrating only on the easiest-to-reach populations and ignoring the more difficult places,” MSF President Joanne Liu said in the report.

“The result of all of this is that people in desperate need of lifesaving assistance are not getting it - because of the internal failings of (the) humanitarian aid system,” Liu added.

The report, which is titled “Where is everyone?,” leveled particular criticism at the United Nations (UN), saying the world body was inflexible and ineffective. In addition, the charity said the UN had a system that “inhibits good decision-making.”

The MSF also examined international emergency response in 2012 and 2013 in South Sudan and the Democratic Republic of the Congo as well as Jordan, where hundreds of thousands of Syrians have sought shelter from deadly violence in their country.

“The UN was at the heart of the dysfunction in each of the cases reviewed,” the report said.

The charity pointed out a number of specific failures, including a lack of water and sanitation in refugee camps in South Sudan, which was left unaddressed for months, contributing to catastrophic death rates.

Furthermore, the report spoke of international staff being evacuated during the worst emergencies, when help was needed the most.

The MSF said it hoped the report could contribute to the discussions about how to improve emergency responses ahead of next year’s World Humanitarian Summit, which has aid effectiveness on its agenda.