US immigration reform talks in the Senate has been stalled over wages for future low-skilled foreign workers say sources.

Newsmax.com reports that bipartisan talks for comprehensive immigration law, including a path to citizenship for undocumented immigrants and a new process for controlling the flow of temporary workers were close to producing a bill after months of discussions.

According to an unidentified source, the eight senators involved in the negotiations has tentatively agreed on a plan to govern wage levels for low-skilled foreigners, such as construction workers, cooks, janitors and hotel maids, in the US on temporary work visas.

The source said Democrats presented a plan and Republicans accepted it, but when senators showed it to the AFL-CIO, the labor union federation said no.

However, according to the AFL-CIO, Democrats presented Republicans with a plan and the Republicans rejected it.

The proposal would have borrowed language on wages for temporary workers from the "H2B" visa program for temporary, seasonal workers, which means that the visas would only be issued if they do not drive down the wages of those doing the same job in the United States.

The inclusion of construction laborers in the plan was also in dispute. Business wants the inclusion, but labor does not.

Randel Johnson, a senior vice president of the U.S Chamber of Commerce, said that "unions have jeopardized the entire immigration reform effort...because of their refusal to take a responsible stance on a small temporary worker program."

Organized labor also expressed frustration over the talks. "There is an uncomprehending level of anger. We have conceded on so many different grounds. They (Republicans) want to pave the path to citizenship with poverty," said Jeff Hauser, a spokesman with the AFL-CIO.

While support from organized labor and the chamber are considered crucial to getting any immigration law through the Congress, senators were still expressing optimism for getting a deal.

One of the eight, Democratic Senator Charles Schumer of New York, said the bipartisan group would meet its end-of-month timetable for a deal and that it would be "an agreement with a darn good chance of becoming law."

Republican Senator John McCain of Arizona, said that while he was "guardedly optimistic" about the talks, "we hit bumps every five minutes."

The eight senators will continue negotiating during the two-week congressional recess.