(Reuters) -The U.S. Trade Representative's office on Wednesday said some of the steep tariff increases on an array of Chinese imports including electric vehicle batteries, computer chips and medical products will take effect on August 1.

President Joe Biden will keep tariffs put in place by his Republican predecessor Donald Trump while ratcheting up others, including a quadrupling of EV duties to over 100% and doubling the duties on semiconductor tariffs to 50%.

The Trade Representatives office said a 30-day public comment period will close June 28. They are seeking comments on the effects of the proposed tariff hike on the U.S. economy, including consumers.

The U.S. Trade Representative said the proposed Chinese tariff hikes "includes products targeted by China for dominance, or are products in sectors where the United States has recently made significant investments."

The new measures affect $18 billion in imported Chinese goods including steel and aluminum, semiconductors, electric vehicles, critical minerals, solar cells and cranes, the White House said. The EV figure, while headline-grabbing, may have more political than practical impact in the U.S., which imports very few Chinese EVs.

For medical products, public comment is being sought on whether the tariffs on face masks, medical gloves, syringes, and needles need to be higher than proposed.

The United States imported $427 billion in goods from China in 2023 and exported $148 billion to the world's No. 2 economy, according to the U.S. Census Bureau, a trade gap that has persisted for decades and become an ever more sensitive subject in Washington.

U.S. Trade Representative Katherine Tai has said the revised tariffs were justified because China was stealing U.S. intellectual property. But Tai has also recommended tariff exclusions for hundreds of industrial machinery import categories from China, including solar product manufacturing equipment.

Ahead of Biden's expected action, China denounced the plan and vowed "resolute measures" to protect its interests. China has said the tariff measures are counter-productive and inflict harm on the U.S. and global economy.

USTR said it would provide details on how companies could apply for machinery exclusions from the tariffs in a separate notice. But it said that any exclusions granted would be backdated to start on Wednesday and end on May 31, 2025