The United States launched an investigation Friday into alleged subsidies of more than $4 billion worth of shrimp exports by seven top global producers that could lead to new import duties.

The US International Trade Administration said the probe would seek to determine whether warm-water shrimp exported to the United States from Thailand, China, Indonesia, India, Ecuador, Malaysia and Vietnam received unfair government support, as the US shrimp industry has accused.

The countervailing duty (CVD) investigation targets mainly farmed shrimp exported frozen to the US, which was valued at $4.2 billion in 2011.

The investigation was launched in response to a complaint by US shrimp harvesters and processors.

The Coalition of Gulf Shrimp Industries said in a December 28 petition to the government that shrimp producers in the seven countries “have gained US market share by aggressively undercutting domestic prices through the use of billions of dollars in assistance from their respective governments.”

“Subsidized imports have suppressed and depressed domestic prices, eroding domestic sales, destroying US jobs, and eliminating the operating margins of domestic producers.”

The International Trade Administration said Thailand was the leading exporter of the seven, shipping $1.6 billion worth of shrimp to the US in 2011.

Indonesia shipped $667 million worth, Vietnam $493 million, India $512 million, Ecuador $524 million, China $154 million, and Malaysia $206 million.

The government plans to make its initial decision on whether to continue the investigations in February. Final determinations could come in July, the agency said.

2013 AFP