EDF Energy will increase its current 300 million pounds a year investment on UK nuclear plants to adopt extra safety rules imposed by Britain's nuclear regulator after the Fukushima nuclear disaster, its chief executive told Reuters on Tuesday.

We will now make over and above current investments to take into account the recommendations on backup systems, openness and transparency and so on. It's something we can afford to do, said Vincent de Rivaz, chief executive of the British arm of France's EDF.

The utility, Britain's largest nuclear operator, will up its nuclear plant spend from the current 300 million pounds yearly, but De Rivaz said a final sum had not been agreed.

Britain's Office for Nuclear Regulation (ONR) in September published a series of safety recommendations to the nuclear industry following lessons learned from Japan's nuclear accident which plant operators have to follow or face station shutdowns.

EDF Energy also plans to build two new third-generation nuclear reactors at Hinkley Point in Somerset, the first new nuclear plant in the UK in nearly twenty years.

The new station's original start-up date of early 2018 has slipped due to regulation delays following Fukushima, but a new deadline will not be made public until the final investment decision is made at the end of next year, de Rivaz said.

It's not a material delay, we will have the interim reactor design approval in 2011, as expected, he said.

The chief executive said earlier on Tuesday that he expected the ONR's interim design approval, a key milestone in the regulatory process, for Areva's European Pressurised Water Reactor (EPR) which EDF Energy will use at its Hinkley Point site.

De Rivaz also said his plan was to follow through one option of using the EPR at Hinkley Point as well as a site purchased at Sizewell to build new nuclear reactors, but added that three years between the Somerset investment decision and the start of Sizewell project planning left plenty of time to talk.

Toshiba-owned Westinghouse has also submitted a reactor design application for approval to the UK regulator and U.S.-Japanese joint venture GE Hitachi also has plans to enter a new-generation design for approval next year.

Next to nuclear plants, EDF Energy has invested in a modern 1,300 megawatts (MW) gas-fired power plant at West Burton in Nottinghamshire, which is planned to open in the first half of 2012.

First fire is expected in January, De Rivaz said, an event which marks the point of the first power production at a new power plant.

The large integrated utility is also facing consequences of Europe's return to economic slowdown, as power demand has not grown as expected, he said.

Everyone is facing turbulent times and we are part of it, he said.

It has an impact, but it's not a turnaround for our business.

(Additional reporting by Adnrew Callus)