By Idrees Ali
WASHINGTON (Reuters) - While the exodus from Syria has become the world's biggest refugee crisis, the United States is being criticized by relief organizations and some within President Barack Obama's Democratic Party for allowing only a limited flow into America.
Since October fewer than 800 Syrian refugees have been admitted into the United States, only a fraction of nearly 4 million displaced from the war-ravaged Middle Eastern country, according to State Department data.
An annual report by the United Nations High Commission for Refugees released on Thursday found that the Syrian refugee problem has for the first time become bigger than that in Afghanistan.
A U.S. State Department official said the total admitted in the last eight months was dramatically higher than in earlier years since the Syria crisis began in 2011. In the whole of 2014 only 249 Syrian refugees were let in.
The official, who spoke on condition of anonymity, said protracted and thorough security checks were in place, which meant an average wait of between 18 months and two years.
Senator Dianne Feinstein, the leading Democrat on the Senate Intelligence Committee, joined 14 other senators who signed a letter to Obama in May calling for more to be allowed in.
David Miliband, president of the International Rescue Committee, said 99 percent of the Syrian refugee burden was being born by neighboring states like Turkey, Lebanon and Jordan, although they had been helped by U.S. and other funding.
"We are confident that appropriate checks can be made in far quicker time to first of all reduce the suffering of the refugees in limbo, but secondly to offer the solidarity that the neighboring countries need," he said.
Larry Yungk, senior resettlement officer at UNHCR, said the U.S. number was expected to rise in the second half of the year.
Rigorous security precautions, including time-consuming identity checks, will continue.
Syria is the headquarters of Islamic State militants who took over much of the country, brutally murdered a number of Americans and other westerners and called for attacks by followers inside the United States.
Representative Michael McCaul, a Republican who is chairman of the House of Representatives Committee on Homeland Security, expressed concern about letting more Syrians in.
"There is a real risk that individuals associated with terrorist groups will attempt to exploit the refugee resettlement program in order to gain entry into our country,” he said in a letter to Obama last week.
(Editing by David Storey and Leslie Adler)