AFP/Washington

President Barack Obama on Tuesday requested $3.7 billion in emergency funding from Congress to help cope with a surge of unaccompanied child immigrants from Central America.

White House officials said the funds, far higher than the president signalled he would request late last month, would help ease an "urgent humanitarian situation" that has seen tens of thousands of minors from El Salvador, Guatemala and Honduras illegally cross the southern US border this year.

The appropriation would go to various US government agencies and would fund an increase in immigration judges, asylum officers and border agents, expand court capacity, and add detention facilities, the officials said.

One main goal is to speed up turnaround times for deportations, with one White House official saying "we are prioritizing recent border crossers."

The funds would also expand the government's Alternatives to Detention program through increased use of methods such as ankle bracelets that would allow migrants to be housed with relatives instead of over-crowded, expensive detention facilities while their cases are being processed.

"We are taking an aggressive approach on both sides of the border," another White House official told reporters, referring to US efforts to speed up the deportation process as well as coordination with Mexican and Central American authorities to prevent migrants from taking the perilous journey to the United States, often with dangerous human traffickers.

"We are taking steps to both protect due process but also to remove these migrants efficiently," said the official, who spoke on condition of anonymity.

According to Obama's emergency supplemental request for fiscal year 2014, which ends September 30, the Department of Homeland Security will receive more than $1.5 billion, including $116 million to pay for transporting migrants back to their home countries.

The Department of Health and Human Services will be allocated $1.8 billion, mostly to provide care for unaccompanied child migrants.

The State Department will also receive some $300 million to help reintegrate Central American migrants to their home countries, address the underlying causes driving migration, and launch media campaigns emphasizing that illegal immigrants will not be allowed to stay in the United States.