Siemens is investing £160 million in two wind turbine production and installation sites in Yorkshire.
The sites comprise the previously announced Green Port Hull project construction, assembly and service facility and a new rotor blade manufacturing facility in nearby Paull, East Riding.
Siemens' port partner, Associated British Ports, (ABP) is investing a further £150m in the Green Port Hull development.
The sites will create up to 1,000 jobs directly, with additional jobs during construction and indirectly in the supply chain.
The Green Port Hull project has been in the making for around four years and is the product of a huge team effort between many national and local political, business and community parties and many people within Siemens in the UK, Denmark and Germany, and ABP.
Siemens said the development would include the first manufacturing plant of its kind for the company's next generation blade technology designed for Siemens SWT-6.0-154 6 megawatt (MW) wind turbine.
Michael Suess, member of the managing board of Siemens AG and CEO of the Energy Sector, said: "Our decision to construct a production facility for offshore wind turbines in England is part of our global strategy: we invest in markets with reliable conditions that can ensure that factories can work to capacity.
"The British energy policy creates a favourable framework for the expansion of offshore wind energy. In particular, it recognizes the potential of offshore wind energy within the overall portfolio of energy production", stated.
"The offshore wind market in Great Britain has high growth rates, with an even greater potential for the future."
Roland Aurich, chief executive of Siemens plc, added: "Being able to further increase our presence in the UK with this significant commitment is great for Siemens, for the UK economy and for future generations, who will benefit from more secure and sustainable, low carbon energy."
Siemens and ABP will be submitting planning applications over the next few months for revisions to the existing proposed scheme at Alexandra Dock and for land in Paull for the wind turbine blade factory.
Green Port Hull is planned to be operational in early 2016. The start of production at the blade factory is scheduled to be in the middle of 2016 with full production levels reached from mid-2017.