Washington (CNN) - Any undocumented immigrant who entered the country after December 31, 2011, will not be eligible for citizenship under terms of the immigration deal set to be unveiled Tuesday by the bipartisan "Gang of Eight" senators, a Senate aide told CNN on Saturday.
Specifics of the program included in the legislation were among the details the eight senators - four Republicans and four Democrats - needed to iron out. Sources with knowledge of the matter told CNN this week the sweeping measure was on track to be unveiled Tuesday.
Members of the Senate Judiciary Committee will hold their first public hearing on the legislation on Wednesday, followed most likely by committee markups in May and consideration by the full Senate in June, according to the sources.
The measure includes a 13-year path to citizenship that could affect up to roughly 11 million undocumented residents, as well as the creation of a system to assess border security.
The path to citizenship would take 10 years for undocumented workers to get a green card, and then another three years to gain citizenship.
Along the way, undocumented workers would have to pay a fine and back taxes and pass a background check. The size of the fine remains unclear.
No undocumented worker would be eligible for citizenship until the border is considered secure - a key sticking point for conservatives.
To measure border security, a commission would be created with the task of establishing and assessing a set of quantifiable criteria. The commission would be made up of officials named by state and federal leaders.
Several key Senate conservatives, including Sen. Jeff Sessions, R-Alabama, remained convinced Friday the group's proposal would be tantamount to amnesty for people who initially entered or have illegally remained in the United States.
"It is likely millions of current and future illegal immigrants ... will benefit from this amnesty," he said in a statement.
The "Gang of Eight" includes Sen. Michael Bennet, D-Colorado; Sen. Marco Rubio, R-Florida; Sen. Lindsey Graham, R-South Carolina; Sen. John McCain, R-Arizona; Sen. Jeff Flake, R-Arizona; Sen. Robert Menendez, D-New Jersey; Sen. Dick Durbin, D-Illinois; and Sen. Chuck Schumer, D-New York.
Viewed as a potential Republican presidential candidate in 2016, Rubio will make a full-court press on the issue on Sunday network talk shows, including CNN's "State of the Union" with Candy Crowley.
His aides said the round of appearances will not include any announcements, but it should be viewed as his "opening argument" on immigration reform.
Democrats and Republicans in the House of Representatives, meanwhile, have been working on their own immigration overhaul plan.
Details of the House blueprint are not yet available. But Florida Rep. Mario Diaz-Balart, a key Republican in the House group, told CNN on Thursday that House negotiators have reached an agreement on the major issues, including border security and a pathway to citizenship.
The congressman declined to give any timeline regarding when a House bill would likely be introduced.
- CNN's Candy Crowley and Jim Acosta contributed to this report.