WASHINGTON — The United States has broadened the reach of its steel and aluminum tariffs, the Commerce Department said on Tuesday, affecting hundreds more products that contain both metals, such as child seats, tableware and heavy equipment.

The Bureau of Industry and Security said in a recent notice that it was adding 407 product types to a list of items considered steel and aluminum "derivative products".

This means a 50 percent tariff on both metals — imposed by President Donald Trump's administration earlier in the year — will apply to their steel and aluminum content.

The widened scope took effect on Monday, and the notice detailing the changes was published in the Federal Register on Tuesday.

"Today's action covers wind turbines and their parts and components, mobile cranes, bulldozers and other heavy equipment, railcars, furniture, compressors and pumps, and hundreds of other products," the Commerce Department said on Tuesday.

The department is also adding imported parts for automotive exhaust systems and electrical steel needed for electric vehicles to the new tariffs, as well as components for buses, air conditioners and appliances, including refrigerators, freezers and dryers.

A group of foreign automakers had urged the department not to add the parts, saying the US does not have the domestic capacity to handle current demand.

Jeffrey Kessler, US under secretary of commerce for industry and security, said the move "shuts down avenues for circumvention", reiterating the aim of boosting the US steel and aluminum industries.

Since returning to the presidency, Trump has imposed a 10 percent tariff on almost all US trading partners, alongside varying steeper levels on dozens of economies such as the European Union and Japan.

Certain sectors have been spared from these countrywide tariff levels but were instead targeted under different authorities by even higher duties.

In the case of steel and aluminum, the administration initially unveiled a 25 percent tariff on imports of both metals before doubling this to 50 percent in June.

Although the influence of the tariffs on consumer prices has been limited so far, economists warn that their full effects are yet to be seen.

For now, some businesses have coped by bringing forward purchases of products that they expected would encounter tariffs. Others have passed on additional costs to their consumers or absorbed a part of the fresh tariff burden.

However, analysts note that importers and retailers will unlikely be able to bear these costs indefinitely, and could eventually raise consumer prices.

Some economists argue that the inflation hit will be one-off, but others are wary of more persistent effects.

Agencies via Xinhua