CAPE TOWN, March 23 (Xinhua) -- South Africa Friday voiced concern over the United States' refusal to exclude it from the application of tariff duties on steel and aluminium.

The imposition of the duties will have a negative impact on productive capacity and jobs in a sector already suffering from global steel overcapacity, South Africa's Department of Trade and Industry (DTI) said.

In addition, South Africa notes with concern the different treatment of trading partners that will affect the competitiveness of South African steel and aluminium products in the United States, the DTI said.

U.S. President Donald Trump earlier this month announced the signing of a proclamation to impose a 10-percent tariff on aluminium imports and a 25-percent tariff on steel.

The proclamation makes provision for country-based exclusions should the U.S. and that country arrive at a satisfactory alternative means to address the threat to so-called U.S. national security.

The European Union (EU) and six other countries namely Argentina, Australia, Brazil, Canada, Mexico and South Korea have been temporary exempted from the tariffs.

The South African government said it had made a formal submission to the United States requesting the exclusion from the duties.

The U.S. Census Bureau data indicates that in 2017 the United States imported a total of 33.4 million tonnes of steel, including about 330,000 tonnes from South Africa, or less than 1 percent of total U.S. imports.

DTI spokesperson Sidwell Medupe has argued that imports from South Africa does not pose a threat to the U.S. national security or industries and that the DTI will pursue further discussions with the United States.