The CFIUS panel itself had also initially been divided over whether it had the right to commence its review before the deal was signed, with representatives from the Departments of Justice, Homeland Security, Defense and Energy urging CFIUS to begin its review of the deal before Qualcomm shareholders went to vote on the slate of directors that included Broadcom's nominees, according to people familiar with the matter.
"The proposed takeover of Qualcomm by the purchaser (Broadcom) is prohibited, and any substantially equivalent merger, acquisition, or takeover, whether effected directly or indirectly, is also prohibited", the presidential order released on Monday said.
Steve Mollenkopf, Qualcomm's CEO, speaks during his keynote address at CES in Las Vegas.
Although its name isn't widely known outside the technology industry, Qualcomm is one of the world's leading makers of the processors that power many smartphones and other mobile devices.
"In both the definitive merger agreement that Broadcom provided to Qualcomm and in the revised version that Qualcomm sent back to Broadcom on February 26, 2018, one of the closing conditions was that Broadcom redomicile to the US, and notably, in neither party's draft was the closing of the proposed acquisition conditioned on CFIUS clearance", the company said in a statement.
Tan has already turned Avago, a small chipmaker with a market value of $3.5 billion in 2009, into a more than $100 billion company.More news: RBI discontinues use of Letters of Undertaking for trade credits
Mr Tan bought California-based Broadcom for $37bn in a deal in 2015 and Brocade Communications in a $5.5bn deal two years later.
According to London, Trump's decision to black Broadcom's hostile takeover of Qualcomm is part of a broader strategy to ensure global US preeminence in technological innovation. There were concerns the takeover could have led to China pulling ahead in the development of 5G wireless technology.
Broadcom has ample firepower for smaller deals, with about US$11 billion in cash and the potential to generate almost US$9 billion in annual free cash flow, analysts estimate.
CFIUS, which raised concerns about the Qualcomm deal with Trump, listed the highly leveraged nature of Broadcom's bid for its larger rival as a major concern coupled with the risk of the US losing mobile technology leadership.
Before Trump's order, Broadcom had planned to relocate its legal headquarters to the United States, avoiding the need for a CFIUS review.
"Given the Chinese influence at least, and ownership, to a certain extent, of Broadcom, and their interest in getting some of this 5G technology, that it is a national security issue, so I think that it's appropriate that CFIUS look at it", Portman told CNBC in an early interview Tuesday.