The number of Syrian refugees registered in Lebanon has exceeded the 1 million mark, in what the U.N. refugee agency calls a "devastating milestone" for a small country with depleted resources and brewing sectarian tension.
Refugees from Syria, half of them children, now equal a quarter of Lebanon's resident population, the United Nations High Commissioner for Refugees (UNHCR) said in a statement, warning that most of them live in poverty and depend on aid for survival.
UNHCR chief Antonio Guterres described the figure as "a devastating milestone worsened by rapidly depleting resources and a host community stretched to breaking point."
Tiny Lebanon has now become the country with "the highest per capita concentration of refugees worldwide" and is "struggling to keep pace," Guterres said in a statement.
"The influx of a million refugees would be massive in any country. For Lebanon, a small nation beset by internal difficulties, the impact is staggering," he said.
Jan Egeland, the secretary-general of the Norwegian Refugee Council, which has 1,000 relief workers in and around Syria, told Al Jazeera that the figure could easily be "more than half a million" higher.
Egeland said not all of the Syrian refugees in Lebanon had officially registered with the U.N., an annual requirement to receive food rations and health and education services. The process can often take months.
"I don't think we are understanding the scope and breadth and magnitude of this crisis," Egeland said. "This is not just another war, this is a generational challenge, and we are not up to meeting that challenge."
Syria's three-year war has so far killed more than 150,000 people, according to the Syrian Observatory for Human Rights, while half of the population are estimated to have fled their homes.
Of those who have fled Syria, nearly 600,000 have registered as refugees in Jordan and around 670,000 in Turkey.
The UNHCR registers 2,500 new refugees daily in Lebanon, it said.
According to Guterres, "Lebanon has experienced serious economic shocks due to the conflict in Syria," while security has deteriorated as a result of rising regional instability.
Al Jazeera and wire services