U.S. President Donald Trump on Wednesday ordered an additional tariff of 25 percent on the imports of certain advanced computing chips, which will become effective Thursday.

In a proclamation posted on the website of the White House, Trump said the tariff shall continue in effect, unless such action is "expressly reduced, modified, or terminated."

"This tariff is in addition to any other duties, fees, exactions, and charges applicable to such imported semiconductors, unless stated otherwise below," the proclamation reads.

Trump cited national security concerns for the tariff on imports of semiconductors. Certain advanced computing chips and certain derivative products described in the proclamation refer to those whose "importation does not contribute to the buildout of the United States technology supply chain and the strengthening of domestic manufacturing capacity for derivatives of semiconductors."

The proclamation includes exemptions, saying the duty rate shall not apply to imports of those covered products for use in U.S. data centers, for repairs or replacements performed in the United States, for research and development in the United States, for startups in the United States, for non-data center consumer applications in the United States, for use in non-data center civil industrial applications in the United States, and for use in U.S. public sector applications.

The exemptions also apply to covered products for other uses that are determined to contribute to the strengthening of the U.S. technology supply chain or domestic manufacturing capacity for derivatives of semiconductors.

Trump ordered U.S. Customs and Border Protection to take any necessary or appropriate measure to administer the tariff imposed by the proclamation to the extent permitted by applicable law, saying no drawback shall be available with respect to the duties imposed pursuant to this proclamation.