Vodafone offered to merge with Verizon Communications prior to the $130 billion sale of its stake in Verizon Wireless, documents seen by Financial Times have confirmed.

A proxy shareholder statement filed by Verizon in New York said that after rejecting the US company’s initial $95 billion offer for the 45 per cent stake in the mobile business in January, Vodafone CEO Vittorio Colao offered to merge the businesses.

The merger option remained on the table until Verizon ruled it out when asked to clarify its intention by the UK financial regulator in April, after which it switched its focus to acquiring Vodafone’s 45 per cent stake.

There followed a period of bartering in which Verizon’s board approved a formal offer of $120 billion in June, with Vodafone demanding $140 billion. However, Colao accepted a “best and final” offer of $130 billion in August.

Bloomberg reported in March that merger discussions had taken place in December 2012 but failed as the companies could not reach agreement on leadership of the combined business.

The documents also reveal that Verizon could pay a break-up fee of up to $10 billion if the deal fails due to financing problems. However, $1.6 billion could go in the other direction if Vodafone shareholders reject the deal in a forthcoming meeting.

If the transaction is not completed by the beginning of May 2014, the purchase price of the deal will increase by $10 million per day.

The deal will see Verizon shares listed in London as well as the New York Stock Exchange and Nasdaq. Vodafone shareholders receiving cash and Verizon stock as part of the deal will end up owning between 29 and 31 per cent of Verizon.

Shortly after the deal was announced, Vodafone outlined its wide-ranging Project Spring investment programme, which was boosted by £6 billion from the Verizon Wireless stake sale.

Between 45 and 50 per cent of this investment will go towards accelerating 4G deployment in Vodafone’s five main European markets with other investment areas including 3G in emerging markets and fixed broadband in Europe.