Sources close to the administration said the rollout would include a televised speech by Obama on Thursday night laying out the plan followed by a trip to Las Vegas on Friday to build support. Nevada is home to the highest proportion of undocumented immigrants in the country.
The White House declined to comment on the specific timing of the announcement but officials have made clear Obama was planning to take executive action soon. Some conservative Republicans have threatened to try to thwart the immigration move by imposing funding restrictions in a must-pass spending bill, which could conceivably raise the possibility of a government shutdown.
Frustrated by years of congressional inaction on what most in Washington agree is a broken immigration system, Obama is planning to issue a reprieve from deportation that will cover some parents of U.S. citizens and legal permanent residents.
That initiative would expand on a 2012 executive order by the president that gave relief from deportation and work permits to undocumented children brought to the United States by their parents.
There is also expected to be a border security element and Obama will act to help companies hire and retain high-skilled workers from abroad, the sources said.
"We've identified a number of ways that we will (fix the system) which the president will speak to in the coming days," Homeland Security Secretary Jeh Johnson said at a National Press Club event on Wednesday.
Obama's move, coming little more than two weeks after elections in which Republicans seized the Senate, is certain to provoke a backlash and House of Representatives Republicans are weighing a range of responses.
Michael Steel, a spokesman for House Speaker John Boehner, said in a statement: "If 'Emperor Obama' ignores the American people and announces an amnesty plan that he himself has said over and over again exceeds his constitutional authority, he will cement his legacy of lawlessness and ruin the chances for congressional action on this issue and many others."