Sessions said he has asked authors of the comprehensive immigration reform bill — the Border Security, Economic Opportunity, and Immigration Modernization Act — exactly how many illegal immigrants would gain legal status under the bill. He said he has not gotten a straight answer, which concerns him because he doesn’t think there's enough job growth to support the new workers.

“I’ve been concerned for some time that the numbers [of illegal immigrants who would get legal status] are too large,” Sessions said. “We don’t have the jobs created to sufficiently employ them. It would only have a negative effect on American workers.”

Sessions serves on the Senate Judiciary Committee, which started the mark-up process of the bill last week and is expected to continue the work throughout May.

The bipartisan group of eight senators, known as the Gang of Eight, introduced S. 744, which would create a pathway to citizenship for illegal immigrants already in the country, toughen border security, create a guest worker program and boost high-skilled immigration.

Some Republicans have complained that the legislation is being rushed through, and that it would provide amnesty for illegal residents before strengthening border enforcement.

Sessions also expressed concern that if the more than 11 million people residing illegally within the United States are given citizenship, they would then be allowed to apply for better jobs that don’t require “under the table” payment. He said this would mean companies could lower wages and unemployment levels would rise.

“I’m asking if we can handle this,” Sessions said. “We really should think about that. … Don’t we owe it to our workers to look at that?”

Sens. Marco RubioMarco Antonio RubioOvernight Cybersecurity: Bipartisan bill aims to deter election interference | Russian hackers target Senate | House Intel panel subpoenas Bannon | DHS giving 'active defense' cyber tools to private sector Senators unveil bipartisan push to deter future election interference Puerto Rico's children need recovery funds MORE (R-Fla.), John McCainJohn Sidney McCainMcCain rips Trump for attacks on press NSA spying program overcomes key Senate hurdle Meghan McCain says her father regrets opposition to MLK Day MORE (R-Ariz.), Lindsey GrahamLindsey Olin GrahamDHS chief takes heat over Trump furor Overnight Defense: GOP chair blames Dems for defense budget holdup | FDA, Pentagon to speed approval of battlefield drugs | Mattis calls North Korea situation 'sobering' Bipartisan group to introduce DACA bill in House MORE (R-S.C.), Jeff FlakeJeffrey (Jeff) Lane FlakeMcCain rips Trump for attacks on press Bipartisan group to introduce DACA bill in House Flake's anti-Trump speech will make a lot of noise, but not much sense MORE (R-Ariz.), Charles SchumerCharles (Chuck) Ellis SchumerDemocrats will need to explain if they shut government down over illegal immigration White House: Trump remarks didn't derail shutdown talks Schumer defends Durbin after GOP senator questions account of Trump meeting MORE (D-N.Y.), Dick DurbinRichard (Dick) Joseph DurbinMcCarthy: ‘No deadline on DACA’ Ex-Sheriff David Clarke: Trump only one who 'cares about black American citizens' DHS chief takes heat over Trump furor MORE (D-Ill.), Bob MenendezRobert (Bob) MenendezCongress must provide flexible funding for owners of repeatedly flooded properties Senate ethics panel resumes Menendez probe after judge declares mistrial Judge declares mistrial in Menendez bribery case MORE (D-N.J.) and Michael BennetMichael Farrand BennetDurbin: Senators to release immigration bill Wednesday Trump's 's---hole' controversy shows no sign of easing Dem senator: 'No question' Trump's 's---hole countries' comment is racist MORE (D-Colo.) comprise the Gang of Eight.

Sessions has been critical of the bill since it was announced that the Gang of Eight was working on legislation. Rubio has called on Sessions and other critics to offer amendments during the committee process in order to improve the bill.

The bill is expected to reach the Senate floor in June.