State-run Korea Electric Power Corp (KEPCO) is building the first of four nuclear plants in the United Arab Emirates in an $18.6 billion deal, and is scouting for more business in Britain and other countries.

But many nuclear experts doubt South Korea's ability to export a technology it is ditching at home after President Moon Jae-in, who took office in May, said he would scrap plans to build new domestic reactors.

South Korea is the world's fifth-biggest user of nuclear energy and KEPCO, which has built more than 20 reactors at home, vies with the likes of France's EDF (>> Electricité de France) and Toshiba's (>> Toshiba Corp) Westinghouse unit in the niche but fiercely competitive nuclear export market.

"Exporting nuclear is an international competition, and Korea will look like a child fighting alone to win a game while others have support from a whole family," said Chung Bum-jin, a nuclear engineering professor at South Korea's Kyung Hee University.

The complexity of nuclear installations meant companies could not rely on past experience for building reactors, said Roh Dongseok, a senior nuclear power policy research fellow at the Korea Energy Economics Institute

"You also need a proven record to revise and upgrade nuclear design. Even if there's a slight change in nuclear design, it is considered as new technology and skills," he said.

Suppliers in Korea, who often produced only small quantities of components, could also face difficulties without the support of a domestic industry, added Chung.

KEPCO's international nuclear project team is working to keep its export business alive.

"We are focussing on the UK market, but also on Saudi Arabia, South Africa and Iran," said Jong-hyuck Park, chief nuclear officer at KEPCO at a recent industry event in London.

KEPCO is also in talks with Japan's Toshiba to buy a stake in Britain's NuGen nuclear project, aiming to use its own reactor design.

"The company (KEPCO) aims to finish the due diligence process by August or September.... and it will take more time to look into South Africa," said a source with direct knowledge of the matter who declined to be identified as he was not authorised to speak to media.

NuGen, planned for Moorside in northwest England, was thrown into doubt after Westinghouse declared bankruptcy and its partner in the project, France's Engie (>> Engie), pulled out.

A KEPCO spokesman said the company is awaiting government guidelines on nuclear exports.

The government's nominee as energy minister has yet to take up the post and it is not yet clear when the government will specify plans for the industry.

"If the South Korean government and industry show a commitment to its exports, it can have a viable and successful nuclear export programme to build on its UAE success," said George Borovas, global head of nuclear at law firm Shearman & Sterling.

(Reporting By Jane Chung; Additional reporting by Susanna Twidale in LONDON and Aaron Sheldrick and Osamu Tsukimori in TOKYO; Editing by Henning Gloystein and Richard Pullin)

By Jane Chung