The U.K. government will look into the national security implications of U.S. group Nvidia's purchase of British chip designer Arm Holdings, it said on Monday, putting a question mark over the $40 billion deal.

Digital minister Oliver Dowden said on Monday he had issued a so-called intervention notice over the sale of Arm by Japan's SoftBank to Nvidia.

"As a next step and to help me gather the relevant information, the U.K.’s independent competition authority will now prepare a report on the implications of the transaction, which will help inform any further decisions," he said.