Verizon is working with several banks to raise $10 billion from each to finance about $60 billion of the deal and an announcement could come as soon as September 2, two sources told Bloomberg.
The stake in Verizon Wireless, the leader in the U.S. mobile market, has become increasingly valuable to Vodafone as its fortunes have waned in its core European markets.
Chief Executive Vittorio Colao said in May he would stake his reputation on selling the stake at the right time and right price and would not bow to pressure to do any deal.
Shares in Vodafone jumped 9 percent to a 12-year high of 207 pence on confirmation of the talks.
Reuters reported in April that Verizon had hired advisers for a possible $100 billion bid and was contemplating a roughly 50:50 cash and stock offer for the 45 percent stake in Verizon Wireless it does not already own.
At the time, most analysts said the roughly $100 billion figure contemplated by Verizon was too low and that the value of the Vodafone holding was nearer $120 billion.
The Wall Street Journal said significant shifts in financial markets, such as rising interest rates as well as changes in the U.S cellphone business had brought the two sides closer together.
A Verizon spokesman declined to comment on the Bloomberg and Wall Street Journal reports.
Vodafone Chairman Gerard Kleisterlee had said last month the company would seriously consider an offer if it offered more value to investors than the current status quo.
Analysts and investors have previously said that structuring the deal to ensure not too much tax was payable by the seller was a tricky issue that needed ironing out so that more of the proceeds would be available to shareholders.
"The tax leakage being rumoured is $10 billion, which I think would be a good result for Vodafone holders," one of the 10 largest investors in the UK-listed telecoms company told Reuters.
© Thomson Reuters 2013
Catch the latest from the Consumer Electronics Show on Gadgets 360, at our CES 2026 hub.