Reform efforts are dead in gridlocked Washington, and fingers of blame are pointing every which way.
Republican opponents of President Barack Obama say his administration has failed to seal the porous US-Mexico border.
Democrats accuse House Republicans of sabotaging the US Senate's bipartisan comprehensive immigration reform bill, which passed with great fanfare one year ago.
That first serious attempt at immigration reform since 1986 imposed a series of tough conditions, including a quasi-militarisation of the border and a boost in quotas for skilled-worker visas.
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Now, the steady increase of minors, illicitly smuggled from Central America and across Mexico into the United States, has further inflamed an already fiery debate.
Democrats warned this week that lawmakers have until their
August recess to work out a legislative solution, or the White House will begin to act on its own.
"We're at the end of the line," said Senate Foreign Relations Committee chairman Robert Menendez, an architect of last year's bill.
"I hope that Speaker Boehner will speak up today," said Senator Dick Durbin.
"And if he does not, the president will borrow the power that is needed to solve the problems of immigration."
Obama could suspend the deportations of thousands of undocumented migrants who can meet certain criteria.
He took a similar step in 2012, just before the presidential election, granting temporary residence permits to youths who arrived before their 16th birthday. He renewed the program, known as DACA, this year for two more years.