The Obama administration's decision this week to ease visa requirements for hundreds of thousands of illegal immigrants represents its latest move to reshape immigration through executive action, even as the White House gears up for an uncertain political fight over a far more sweeping legislative package in the months ahead.

Immigration advocates on Thursday hailed a rule change at the Department of Homeland Security that would make it easier for many undocumented immigrants to stay in the United States as they seek permanent residency, saying it will improve the lives of relatives who could have been separated for years without the changes.

For President Barack Obama — who has called the inability to achieve comprehensive immigration reform among the biggest regrets of his first term — the new policy is among a series of steps his administration has taken over the past year aimed in part at easing the pace of deportations, which have surged during his tenure.