Six leading investors have said $100 billion is not a high enough price for Verizon to pay Vodafone for its 45 per cent stake in Verizon Wireless, according to Reuters. Instead the US operator should stump up at least $120 billion, say the Vodafone shareholders.

A report last week said Verizon was preparing a $100 billion offer for Vodafone’s stake. Based on the investor poll, that offer would face rejection. In fact, in such a situation investors would favour a full merger between the two companies, although that was ruled out earlier this month by the US company.

Investors expressed concern that selling the Verizon Wireless stake would leave Vodafone over-exposed to the slow-growing European market.

The UK operator receives not just a share of Verizon Wireless’s profits but also a dividend payment from its investment.

The $120 billion figure is at the bottom end of what investors consider acceptable. The high end of what they might expect is $135 billion.

Another crucial factor dictating the viability of any deal is the tax terms. Another Reuters report says that Verizon may have found a way to avoid a big chunk of the massive US capital gains tax bill that would otherwise fall to Vodafone following any deal.

For example, the tax on a $100 billion deal for Vodafone would be in the region of $38 billion, according to UBS Investment Research.

However, the hefty tax bill is based on Verizon acquiring the 45 per cent in Verizon Wireless held by Vodafone Americas, which is a US holding company. Instead, sources said Verizon is thinking about an alternative tactic that would involve buying Vodafone Americas outright because its owner is not a US company, so reducing the tax payment due.

There is a second part of any such deal since Vodafone Americas also owns some of Vodafone’s non-US assets. These would be sold back to their parent, incurring a tax bill for Verizon of $5 billion or less.