A US solar industry group opposed to a rival coalition's request for steep import duties on Chinese-made solar cells and modules warned in a report on Monday that more than 60,000 US jobs could be lost if such duties were imposed.

"We cannot allow one company's anti-China crusade to threaten the US solar industry and tens of thousands of American jobs," said Jigar Shah, president of the Coalition for Affordable Solar Energy (CASE).

The CASE report, commissioned from The Brattle Group, an economics consulting firm, says the job losses would come in the solar industry and in the broader US economy, even though there would be a gain in domestic solar manufacturing jobs.

CASE says it represents companies responsible for 97 percent to 98 percent of US solar industry jobs, which it defines to include residential and commercial installation of solar panels as well as domestic manufacturing.

The group strongly opposes a request for anti-dumping and countervailing duties on Chinese-made solar cells and panel filed by SolarWorld Industries America, the US arm of one of Germany's largest solar manufacturers.

SolarWorld, along with six other US solar energy companies who have remained anonymous, has asked the US Commerce Department to impose duties of more than 100 percent on their Chinese competitors to offset alleged government subsidies and unfair pricing practices.

The department had been expected to announce preliminary countervailing duties in the case on Feb 14, when China's Vice President Xi Jinping, meets with President Barack Obama at the White House.

A Commerce Department official said on Monday the initial ruling has been delayed until March 5.

But the department has made a preliminary finding of "critical circumstances" in the countervailing duty investigation, meaning any duties announced on March 5 would be applied retroactively from early December, the aide said.

A second critical circumstances finding would have to be made for any anti-dumping duties to be applied retroactively, the aide added. Commerce is expected to announce preliminary anti-dumping duties in late March.

US imports of the solar energy products from China have soared in recent years and were expected to exceed $2.4 billion in 2011, up from about $1.5 billion in 2010.

The Solar Foundation, a nonprofit education and research organization, estimated in August there were slightly more than 100,000 Americans working in the solar industry and forecast 24,000 new jobs would be added in the coming year

The Brattle Group study estimated a 50-percent tariff would shut out most imports from China, driving up prices for solar panels, pushing down demand and resulting in 14,877 to 43,178 fewer US jobs by 2014 than would be expected without duties.

A 100-percent tariff would completely block imports from China, threatening 16,917 to 49,589 jobs by 2014, it said.

Polysilicon is a key material used to make photovoltaic solar cells.