Definition: The UN differentiates between refugees --- those who cross borders and those who do not; the latter are the subject of much contention.

The U.N. for a variety of political and financial reasons, distinguishes between refugees who have crossed international borders to escape conflicts and those who leave their homes but remain in their countries.

These so-called “internally displaced people” often fall through the care cracks and receive less aid than refugees, who are protected under well-established humanitarian conventions.

On Thursday at the request of the US, the Security Council held an open debate on the issue, which has grown more contentious in recent years as the number of internally displaced surpasses the number of refugees across the globe.

The UN estimates there are between 14 million and 15 million refugees worldwide.

Another 20 million to 25 million are internally displaced people, or IDPs --- half of them in Africa.

“These are people. And to a person who has been driven from his or her own home by conflict, there is no difference between being a refugee or an IDP in terms of what happened to them,” US Ambassador Richard Holbrooke told the council.

The UN High Commissioner for Refugees was created 50 years ago specifically to care for and protect refugees.

At the time, refugees from Cold War-related conflicts between countries fueled mass population shifts across borders.

Today, however, most conflicts are internal and the population shifts occur within individual countries.

While the internally displaced enjoy many of the same protections as refugees, UNHCR’s mandate and resources --- already stretched thin caring for refugees --- enable it to care for only about 5 million of the world’s internally displaced.

Other UN agencies, such as the World Food Program and UN Children’s Fund, often work in ad hoc arrangements with the International Committee of the Red Cross to care for uprooted people who don’t leave their countries when they become refugees.

But even these arrangements don’t always work.

Governments may for various political reasons be unwilling to accept international assistance, as is the case in Myanmar, Turkey and Algeria, Roberta Cohen, a guest scholar at The Brookings Institution, told a press conference.

In these cases, the government may consider the civilians to be part of the conflict, and citing its sovereignty, deny them international aid.

“Their own state authorities or rebel forces in control are frequently the very cause of their predicament,” British Ambassador Jeremy Greenstock told the council.

The UN High Commissioner for Refugees, Sadako Ogata, told council members that urgent action must be taken in Central Africa in particular “to compensate for the lack of protection mechanisms for internally displaced people.”

“The worst pages of colonial history seem to live once more in situations in which people struggle to survive while small groups benefit from Africa’s wealth,” she added.

Holbrooke called for the UN to “erode if not erase” the distinction between refugees and internally displaced people and put responsibility for both under a single agency.

“I recognize that the distinction raises complex legal issues of international sovereignty,” Holbrooke said.

“But let us remember that individual lives are at stake.”

Canada’s deputy UN Ambassador, Michel Duval, however, said such arguments didn’t hold up. “Where countries cannot or do not want to provide necessary assistance to their populations, they nevertheless have responsibility to provide full access to them for others so that their basic needs can be met,” Duval said.