Business and labor groups have reached an agreement on a temporary worker program, a final major sticking point in negotiations over a draft comprehensive immigration reform bill.
A source with knowledge of the negotiations confirmed the deal reached in principle to NBC News.
The AFL-CIO and the US Chamber of Commerce had been tussling over wages for temporary workers authorized to work in the United States in industries such as construction and hospitality.
According to the AFL-CIO, the deal reached would create a new "W" visa program for temporarily year-round low-skilled foreign workers as well as a new "Bureau of Immigration and Labor Market Research" that would make recommendations about the program to Congress.
The program, scheduled to go into effect in 2015, would start at 20,000 visas, increasing in subsequent years up to as many as 200,000 visas per year.
The number of visas granted would fluctuate based on an economic formula that would take into account unemployment and the Bureau's recommendations. Businesses would be required to pay the temporary workers at the same rate as others performing the same job, or at the prevailing wage for the occupational category they are in – whichever is greater.
Workers would be eligible to petition for legal residency after one year.
The union originally advocated for fewer temporary worker visas granted annually and for higher guaranteed wages for such workers, which it said would prevent the driving down of pay for similarly situated American workers. The Chamber had lobbied for more flexibility for businesses employing temporary workers during labor shortages.
A source close to the negotiations calls this a major development but says there is still work to be done on the larger deal. They are still planning to unveil the entire immigration reform package the week of April 8.
The deal helps clear the way for a bipartisan Senate draft of immigration legislation, which lawmakers in the so-called "Gang of Eight" have been working on behind closed doors.
While they are not giving specifics yet, both sides agreed to a complex system of payment which takes into account a number of factors including the unemployment rate. The labor unions are happy because they think the system won't have a net drag on the salaries of American workers, and the Chamber doesn't feel as as though they will be overpaying for entry level jobs.
"The senators will make the decisions about any final agreements and what makes the best public policy overall," Chamber of Commerce communications director Blair Latoff Holmes said.
A White House official said President Barack Obama is encouraged by the progress made by the bipartisan group of senators.