WASHINGTON, June 11 (Xinhua) -- Using "a combination of tariffs and tough negotiating tactics," the Trump administration's trade approach is creating great uncertainty and hurting American businesses, Thomas J. Donohue, president and CEO of the U.S. Chamber of Commerce, said on Monday.

"We have reminded them that a tariff is nothing more than a tax, and it is not paid by the exporting country -- it is paid by the American people," Donohue wrote in an article posted on the business group's official website.

"The growing list of tariffs proposed or imposed by our government, as well as the continued uncertainty over the future of NAFTA (North American Free Trade Agreement), is already taking a toll on businesses," he said.

Donohue said that U.S. steel prices have risen nearly 40 percent since January and higher material costs have suddenly become "a substantial concern" for contractors.

"If these actions continue, our businesses will lose customers, workers will lose jobs, and American consumers will lose family income through higher taxes and higher prices," he said.

Citing national security concerns, the Trump administration has slapped heavy tariffs on steel and aluminum imports and initiated an investigation into automobile imports, drawing strong opposition from the domestic business community and U.S. trading partners.

"Studies show that a combined 760,000 jobs could be lost from the tariffs already enacted as well as those being considered on autos and auto parts," Donohue said, adding an additional 1.8 million U.S. jobs could be lost in the first year alone if the Trump administration carries out its threat to withdraw from NAFTA.

The administration's trade approach "runs the risk of erasing the recent economic gains it worked so hard to secure through tax and regulatory relief without even solving the underlying problems," said the U.S. Chamber's president.