Broadcom is preparing to unveil an unsolicited offer to buy Qualcomm for as much as $70 a share in cash and stock tomorrow morning, in a bold bid to become a dominant supplier of communications chips to the wireless industry, people close to the situation told CNBC on Sunday.

The $70 a share bid, equal to more than $103 billion, will be comprised of at least 75 percent in cash, and will also include Broadcom’s willingness to have Qualcomm complete its pending acquisition of NXP Semiconductors for more than $38 billion in cash.

Qualcomm’s stock, traded on the Nasdaq, surged by more than 12 percent on Friday amid speculation that Broadcom was preparing a bid. It finished the session at $61.81.

Broadcom’s advisers were huddled in the mid-town Manhattan offices of its law firm Wachtel Lipton late Sunday afternoon deciding on final steps for the roll-out of its offer.

Broadcom has been working on its proposal for months and is believed to have approached Qualcomm privately about its offer, but was quickly rebuffed. The company had originally considered an attempt to buy Qualcomm prior to that company’s deal to buy NXP more than one year ago, but upon getting no traction at that time, retreated.

This time, Broadcom is determined to bring its offer to the attention of Qualcomm shareholders. People familiar with the company’s thinking indicate Broadcom will not shy away from initiating a proxy fight to gain seats on Qualcomm’s board of directors in support of its offer.

Qualcomm’s annual meeting is currently scheduled for March of next year with the deadline for nominating directors some time in December.

Qualcomm, however, is expected to strongly resist Broadcom’s proposal. People close to the company expect it to indicate the offer price of $70 is far below what it would expect in a takeover. In addition, Qualcomm is expected to raise concerns that any combination with Broadcom would raise significant antitrust concerns.

While Broadcom is expected to indicate its willingness to let Qualcomm complete its deal to acquire NXPI, it is also expected to encourage the company not to raise its current $110 cash deal to acquire the company. Qualcomm is under pressure from NXP shareholders to raise its bid for that chip company, or face the likely prospect it will not be able to meet the minimum threshold needed to take control of the company under Dutch law.

Officials at Qualcomm and Broadcom declined comment.