* Bourse listing could value GTT at up to $2.4 billion
* GTT is world leader in cryogenic hull membranes for LNG ships
* Korean shipyards considered bid last year (Adds CEO quotes, background)
PARIS, Nov 22 French gas and power group GDF Suez is working on a stock market listing for its Gaztransport & Technigaz (GTT) subsidiary, Chief Executive Gerard Mestrallet confirmed on Friday.
Sources told Reuters in June that shareholders of GTT, the world's No. 1 maker of cryogenic hull linings for tankers that carry liquefied natural gas (LNG), were planning an initial public offering (IPO) that could value the business at up to $2.4 billion.
"The decision has not yet been taken, but I can confirm that we are working on it," Mestrallet told reporters at the Actionaria shareholders conference.
He added that GDF would certainly remain a GTT shareholder.
GDF Suez is a major LNG shipper and the leading shareholder of GTT with a 40 percent stake. French oil major Total and private equity fund Hellman & Friedman each also own 30 percent of GTT.
Financial daily Les Echos this week reported that an IPO is scheduled for February and that the shareholders had not yet decided how much of their stakes they wanted to sell.
GTT has 70 percent of the market for the high-tech alloy membranes that line the hulls of the world's LNG tankers. Its main customers are Korean and Chinese shipbuilders who pay GTT up to $10 million per ship.
GTT and Norwegian rival Moss Maritime have a virtual duopoly in the lucrative niche market, despite attempts by Korean shipbuilders to develop their own cryogenic technology.
GTT last year earned a net profit of 30 million euros on sales of 90 million and expects turnover to more than double this year to 200 million euros ($271 million). ($1 = 0.7394 euros) (Reporting by Benjamin Mallet,; Writing by Natalie Huet and Geert De Clercq; Editing by David Goodman)