The move won’t affect Siemens’ $600 million manufacturing hub in Hull, which is under construction and should producing blades and turbines for offshore next year, but future investments are off the table.

The firm’s UK CEO Juergen Maier told The Guardian that could mean plans to export components from Hull to Europe were likely to be abandoned.

“Those plans were only beginning to happen and I expect that they will stall until we can work out exactly what the [new government’s] plan is, how we can participate in EU research programmes, and until all the issues around tariffs and trade have been sorted out,” he said.

The European Union is believed to have partially funded the Hull expansion, and it has also pumped more than $1 billion into the Beatrice windfarm project in Scotland, whose developers - SSE (40%), Copenhagen Infrastructure Partners (35%) and SDIC Power (25%) - will be a major buyer of the Hull factory’s turbine blades.

Beatrice, which was only approved in May, is designed to be a 588 megawatt, 84 turbine, wind farm situated in the Outer Moray Firth that will power some 450,000 homes, around three times the number of homes in the Moray and Highland regions.

Construction of a new $20 million operations and maintenance facility in Wick and the transmission works in Moray will commence this year and offshore construction is expected to begin next year, with operations beginning in 2019.

The development is expected to deliver some $1.3 billion in injections to the UK and Scottish economy via employment and supply chain opportunities during the construction phase and between $800 million and $1 billion during the wind farm’s 25 year operational life.

But, while Beatrice is unaffected, the fate of a contract between Siemens and a Belgian consortium, which received a $500 million loan from the European Investment Bank for the supply, servicing and maintenance of 42 offshore turbines remains less clear.

Maier said companies such as Siemens and the wider wind power sector require more clarification around now the UK’s exit from the EU before the UK parliament triggers Article 50, which begins a two year process to leave the union.

“People will be holding off on major investment decisions and this is why we need to get together as soon as possible and see that a plan is put in place,” he said.

The UK will need to renegotiate new trade arrangements with the EU, or it will automatically roll over into World Trade Organisation rules, which could pose issues for many companies, particularly in the energy space, and could see tariffs enacted.

Industry figures expect the vote to have a detrimental effect on the energy union process of linking Europe’s electricity grids so that clean power can be transferred across borders in real-time, without need for storage.

There are also concerns that the EU’s target of a 27% share for renewable energy, averaged across Europe by 2030, could now be too ambitious.

The UK has outperformed several EU states in attracting investors, last year taking some $50 billion - around half of all Europe’s wind energy investment.