President Donald Trump issued an executive order yesterday blocking Broadcom’s $117 billion hostile takeover bid for Qualcomm. The move puts an end to what potentially could have been the biggest tech merger of all time. The combination of the two semiconductor companies would have created a powerhouse that makes chipsets for smartphones, computers, and an array of connected devices.

The action is thought to be an extraordinary move by the president and one that reflects the Trump Administration’s concerns about national security. The executive order stated that the reason for blocking the deal was that there is “credible evidence” that Broadcom, through its control of Qualcomm, might impair the national security of the United States.

It also demonstrates the increasing competition between the U.S. and China over technological advances. Qualcomm has been a strong proponent of 5G and has pushed the 3GPP standards body to advance the 5G standardization process.

The order was signed just hours after Broadcom sought to avoid the purview of the Committee on Foreign Investment in the United States (CFIUS) by accelerating its relocation of its headquarters from Singapore to the United States. Broadcom said yesterday that it would speed up its relocation plans and have its headquarters in the U.S. by April 3, two days before Qualcomm’s rescheduled annual meeting of stockholders where Broadcom hoped to put its directors up to a vote. Previously, Broadcom said it would redomicile from Singapore to the U.S. by May 6.

Qualcomm issued a statement saying that all of Broadcom’s director nominees are now disqualified from being elected as directors of Qualcomm. The company also said that it would reconvene its 2018 annual meeting of stockholders on March 23.

Many in the industry reacted favorably to the news because of Qualcomm’s heavy emphasis on research and development, which Broadcom was not likely to continue.

“This should be viewed as a very positive event not only for Qualcomm but also for the market as a whole. The combined entity would have had dangerously dominant positions in some core markets such as location technologies, WiFi, Bluetooth, RF hardware, and automotive semiconductors," said Stuart Carlaw, chief research officer at ABI Research. "A diverse supplier ecosystem will be key to supporting the IoT as well as vertical market developments such as smart mobility and smart manufacturing.”