The delayed multi-billion pound Hinkley Point nuclear power station will definitely go ahead, the head of French giant EDF assured MPs today.

Vincent de Rivaz, chief executive of the firm behind the project, admitted it had been a "long road", but insisted confidence in the £18 billion project remained.

He told the Energy and Climate Change Committee "clearly and categorically" Hinkley Point C will be built.

French economy minister Emmanuel Macron has said EDF will make a final investment decision on Hinkley Point in early May.

Mr de Rivaz said the project had successfully passed regulatory, political, commercial and operational milestones.

EDF had invested £2.4 billion in the project and continued to spend £55 million a month, he said.

Asked about a date for the long-awaited final investment decision he said it would be "soon", referring MPs to the early May date announced by the French minister yesterday.

He told the committee that EDF had the expertise to build the power station, the supply chain was ready and commercial partners were in place.

Mr de Rivaz said everyone was working on the final stage to "make it happen" but, despite being pressed by MPs, he declined to give an actual date for the final investment decision.

"This project is absolutely critical and has the full support of the French government and the British government. Everything is aligning at the moment - it is very positive."

EDF will bear any risk from the project, he said.

Mr de Rivaz reiterated that the cost of the project would definitely be £18 billion.

Humphrey Cadoux-Hudson, managing director of nuclear new build for EDF Energy, told MPs that the cost of decommissioning the power station was being factored into the project.

A fund will be set up, similar to a pension scheme, with money being set aside every year.

Mr de Rivaz said it was the first time this was being done for a nuclear power station.

"It is an example of us and the UK Government behaving in a very responsible way."

Responding to EDF's evidence, Doug Parr, Greenpeace's chief scientist, said the UK's energy policy had been "annexed" by EDF.

"It became very clear that Hinkley is dependant on the French state and the enthusiasm of the French and Chinese nuclear industries.

"This has distorted our national infrastructure planning, and has led to the UK government undermining our nascent but booming renewable energy businesses and scaring off investment."

Shadow energy secretary Lisa Nandy said: "Britain's energy security now appears to be in the hands of the French and Chinese governments. The Energy Secretary must urgently come to Parliament and explain to MPs what her plan is to keep the lights on and meet our climate change commitments if this huge new power station does not get built."

A spokesman for the Department of Energy and Climate Change said: "Good progress continues to be made so that Hinkley can provide clean, affordable and secure energy that families and businesses can rely on now and in the future."