Mobile phone carrier Vodafone has warned that it could move its headquarters abroad following the UK’s vote to leave the European Union.

The British public voted 52:48 to leave the EU last week, causing shockwaves in global markets.

Vodafone, the seventh-biggest company on the FTSE 100 with a stock market value of £55billion, employs 13,000 people here.

It has its HQ in London – but is worried about the consequences of Brexit.

"The UK's membership of the European Union has been an important factor in the growth of a company such as Vodafone," a company spokeswoman said.

"It remains unclear at this point how many of those positive attributes will remain in place once the process of the UK's exit from the European Union has been completed.

“It is therefore not yet possible to draw any firm conclusions regarding the long-term location for the headquarters of the group."

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She stressed that a "very large majority" of the parent company's 462 million customers, 108,000 employees and 15,000 suppliers are based abroad, suggesting that there is no reason for Vodafone’s HQ to remain on these shores.

Most of Vodafone group’s revenue is generated on the continent, with just one tenth coming from the UK.

Britain faces a drawn-out period of trade negotiations as it seeks to remain in the single market, a goal openly mocked by some senior politicians in Brussels.

She added that pan-European businesses rely on freedom of movement of people, capital and goods but said Vodafone would "continue to invest in our UK local operating company in future".