The White House is finalizing additional restrictions on the export of artificial intelligence microchips that would hit companies including Nvidia and Advanced Micro Devices, according to a report.

Bloomberg, citing people familiar with the matter, said the restrictions would be on the sale of AI chips used in data centers and would expand restrictions to most of the world. The regulations, which could be issued on Friday, would create three tiers of chip curbs, the report said - with the top tier of U.S. allies getting unmitigated access, another group getting blocked, and the vast majority subject to country-level limits.

Countries would be able to increase their limits by agreeing to a set of security and human rights standards, the report said. The report quoted Nvidia's opposition to the plan, with the chip maker calling it a major shift in policy that would threaten economic growth and U.S. leadership.

Nvidia and AMD already are limited in their ability to sell to China and Russia.

In after-hours trade on Wednesday, Nvidia (NVDA) and AMD (AMD) each fell 1%. U.S. markets are closed Thursday for President Jimmy Carter's funeral.

-Steve Goldstein

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