WASHINGTON (Reuters) - The U.S. Commerce Department on Wednesday announced a preliminary finding that imports of large-diameter welded pipe from China, India, South Korea and Turkey were subsidized by those countries, and said it was imposing preliminary duties that could top 500 percent.
The Commerce Department opened an investigation in March into whether six countries, including Canada and Greece, were dumping the pipe, which is typically used to build oil and gas pipelines, in U.S. markets or were being unfairly subsidized by their governments.
The probe is one of more than 100 cases that President Donald Trump's administration has opened since taking office that are aimed at protecting U.S. manufacturers in global markets.
The United States' increasingly aggressive stance has been denounced by key trading partners and some Americans who warn it could lead to an economically damaging trade war.
The Commerce Department on Wednesday said it was imposing preliminary anti-subsidy duties on imports of the pipe from India of up to 541.15 percent and on those from China of up to 198.49 percent.
Pipe imports from South Korea will face countervailing duties from 0.01 percent up to 3.31 percent, and from Turkey from 1.08 percent to 3.76 percent.
Imports in 2017 of large-diameter welded pipe were valued at an estimated $29.2 million (£22.1 million) from China, $294.7 million from India, $150.9 million from South Korea and $57.3 million from Turkey, Commerce figures show.
The Commerce Department launched the investigation after a petition from a group of privately held U.S. producers. The probe covered welded carbon and alloy steel pipe larger than 16 inches (406.4 mm) in diameter.
Commerce earlier estimated dumping margins on the pipe at 50.89 percent for Canada, 120.84 percent to 132.63 percent for China, 41.04 percent for Greece, 37.94 percent for India, 16.18 percent and 20.39 percent for South Korea, and 66.09 percent for Turkey.
"Dumping" is the practice of selling goods below market price.
The U.S. International Trade Commission is scheduled to make a final decision by Dec. 20 on whether the subsidies harm U.S. producers, after which Commerce may issue countervailing duty orders that typically run for five years.
(Reporting by Eric Walsh; editing by Phil Berlowitz and Leslie Adler)