As Britain steps up the hunt for a new partner for a stalled nuclear power project, South Korea’s Kepco remains the most likely suitor, but two people with direct knowledge of the matter said the giant utility won’t be rushed to the altar.

With British business minister Greg Clark in Seoul for talks, the status of Kepco - Korea Electric Power Corp (Kepco) – as likely buyer has been enhanced this week by troubled Japanese conglomerate Toshiba Corp having to take on full ownership of the NuGen project after France’s Engie backed.

One of few utilities to retain global nuclear ambitions, Kepco said last month that it was in talks over a potential stake purchase in NuGen, a three-reactor, up-to-3,800 megawatt project in northwest England that London needs on stream in 2025 to meet projected power demand, but has suffered significant setbacks since it was set up in 2010.

But while both Britain and cash-strapped Toshiba seek to accelerate progress towards a deal, state-owned Kepco will not be able to move faster, the people with direct knowledge of the matter said. They declined to be identified because they were not authorised to discuss the matter publicly.