More than 1.5 million Syrians have fled their conflict-ravaged homeland, the UN's refugee agency said Friday, warning that the real figure could be even higher as the tally only reflected those who register with aid groups.
Dan McNorton, spokesman for the UN High Commissioner for Refugees, told reporters that close to 250,000 Syrians were being registered each month.
"Refugees tell us the increased fighting and changing of control of towns and villages, in particular in conflict areas, results in more and more civilians deciding to leave," McNorton said.
"Over the past four months we have seen a rapid deterioration when compared to the previous 20 months of this conflict," he added.
McNorton underlined that the actual number of refugees was likely to be even higher than 1.5 million.
"This is due to concerns that some Syrians have regarding registration," he said, explaining that rumours circulating among exiles about the supposed security risks of signing up for refugee status put some people off.
He said aid agencies were working to encourage waverers to register in order to be able to receive official help, even as UNHCR struggles to keep up with the rising numbers and needs.
"The increasingly widening gap between the needs and resources available is a growing challenge," he said.
"UNHCR continues to respond to the emergency needs of those in desperate need inside Syria and neighbouring countries," he added.
Syrians have surged out of their country since March 2011, when a crackdown on protests against the regime of President Bashar al-Assad heralded the start of an armed rebellion.
Numbers ballooned as the conflict morphed into an increasingly sectarian civil war, and the total topped a million in March this year.
Most have fled to neighbouring Jordan, where close to 474,000 have been registered by UNHCR or are waiting registration, and to Lebanon, with over 470,000.
Some 347,000 are in Turkey, over 147,000 in Iraq and close to 67,000 in Egypt, according to UNHCR's latest data.
In addition to the refugees, the United Nations has said that more than 4.25 million Syrians are displaced within their homeland.
That means that, all told, over a quarter of Syria's pre-war population of 22.5 million have been forced to quit their homes since the conflict began.
The death toll has surpassed 90,000, according to the UN.