Vodafone has selected UBS, while Telecom Italia (TIM) has chosen Banca IMI, Goldman Sachs and Bank of America Merrill Lynch, one of the sources told Reuters on Wednesday.

TIM, Vodafone and the banks all declined to comment.

TIM and Vodafone agreed in July to fold their Italian mobile tower assets into TIM's 60%-owned unit INWIT to cut debt and free up cash for the roll-out of next generation 5G telecommunications networks.

The 10 billion euro (£8.59 billion) merger deal is awaiting European Union antitrust approval and is expected to wrap up in the first few months of 2020.

INWIT, Italy's biggest telecom mast operator, has called a shareholder meeting on Dec. 19 to sign off on the deal.

After the merger TIM and Vodafone will have 37.5% each of the new bigger INWIT but the two phone groups have already agreed to cut their stakes to 25%, while keeping joint control.

The two phone companies are expected to kick of the process to sell the stake in the coming days, one of the sources said.

Several European telecom companies are considering selling part of their mobile networks on the back of high valuations for infrastructure assets and a growing appetite from funds seeking steady returns at a time of negative rates.

Earlier this month, France’s former telecoms monopoly Orange said it plans to carve out its mobile towers in most European countries where it is present.

By Elvira Pollina and Stephen Jewkes