WASHINGTON -- Prospects for a U.S. Senate deal on an ambitious overhaul of America's immigration laws improved markedly as business and labour appeared ready to set aside their differences over a new low-skilled worker program holding up the agreement.

The AFL-CIO trade union confederation and U.S. Chamber of Commerce had been fighting over wages for tens of thousands of low-skilled workers who would be brought in under the new program to fill jobs in construction, hotels and resorts, nursing homes and restaurants, and other industries.

But on Friday, officials from both sides said there was basic agreement on the wage issue, and Democratic Sen. Chuck Schumer said a final deal on the low-wage worker dispute was very close.

That likely would clear the way for Schumer and seven other senators in a bipartisan group to unveil legislation the week of April 8 to overhaul the U.S. immigration system, strengthening the border, cracking down on illegal employers, allowing in tens of thousands of new high- and low-skilled workers, and providing a path to citizenship for the 11 million illegal immigrants already in the country.

"We're feeling very optimistic on immigration: Aspiring Americans will receive the road map to citizenship they deserve and we can modernize 'future flow' without reducing wages for any local workers, regardless of what papers they carry," American Federation of Labor-Congress of Industrial Organizations (AFL-CIO) spokesman Jeff Hauser said in a statement. "Future flow" refers to future arrivals of legal immigrants.

Under the emerging agreement between business and labour, a new "W" visa program would bring tens of thousands of lower-skilled workers a year to America. The program would be capped at 200,000 a year, but the number of visas would fluctuate, depending on unemployment rates, job openings, employer demand and data collected by a new federal bureau pushed by the labour movement as an objective monitor of the market.

The workers would be able to change jobs and could seek permanent residency. Under current temporary worker programs, workers can't move from employer to employer and have no path to permanent U.S. residence and citizenship. And currently there's no good way for employers to bring many low-skilled workers to the U.S. An existing visa program for low-wage nonagricultural workers is capped at 66,000 per year and is supposed to apply only to seasonal or temporary jobs.

The Chamber of Commerce said workers would get paid the same wages paid to American workers or the prevailing wages for the industry they're working in, whichever is higher. The Labor Department determines prevailing wage based on rates prevailing in specific localities, so that it would vary from city to city.

The low-skilled worker issue had loomed for weeks as perhaps the toughest matter to settle in months-long closed-door talks on immigration among the senators, including Republicans John McCain of Arizona and Marco Rubio of Florida. The issue helped sink the last major attempt at immigration overhaul in 2007, when the legislation foundered on the Senate floor after an amendment was added to end a temporary worker program after five years, threatening a key priority of the business community.

The amendment passed by just one vote, 49-48. President Barack Obama, a senator at the time, joined in the narrow majority voting to end the program after five years.