General Electric has said it will receive $1.9bn (£1.4bn) for a contract to supply steam turbines, generators and other equipment to the controversial Hinkley Point C nuclear power plant in Somerset.
It comes a day after the £18bn project was approved by the government following the conclusion of a review which was initiated after Theresa May came to power in July.
The decision paved the way for the US firm to start building two 1,170-megawatt Arabelle steam turbines and generators, Reuters reported.
GE had already been doing early engineering work on the project after acquiring the contract when it bought the power assets of French engineering firm Alstom last year. Alstom had won the competition in 2013.
The UK decision "confirms our technology leadership and it also confirms it was not such a bad decision to buy Alstom," Andreas Lusch, chief executive officer of steam power systems at GE Power, told Reuters.
Plans to build Britain's first new nuclear power plant in decades has been dogged by concerns over its cost, security and deliverability.