South Korea's LG Display Co Ltd said on Friday that its head of TV business will take over as chief executive in 2012 in a surprise announcement as the flat-screen maker struggles with mounting losses and weak demand.

Han Sang-beom, executive vice-president and head of the TV division, will take over from Kwon Young-soo, who will move to LG Chem Ltd to lead the company's rechargeable battery business.

This new executive nomination is entirely on the basis of performance in strengthening LG Display's global business capabilities, the company said in a statement.

The top management change at LG Display, which vies with local rival Samsung Electronics Co for the title of the world's top flat-screen maker, comes as the firm reported its biggest quarterly loss in the third quarter, hit by tumbling panel prices and tepid demand for TVs and computers.

Kwon became LG Display's chief executive in 2007 after serving as chief financial officer for its electronics affiliate LG Electronics Inc, where he helped it secure foreign funds and form the flat-screen venture with Philips in the wake of the Asian financial crisis in late 1990s.

Philips later sold the stake back to LG.

The 32-year veteran of LG business conglomerate has been widely credited for boosting the panel maker's global ranking and its profitability during one of the industry's worst downturns in 2007, and winning major customers such as Apple Inc.

LG Display is a major supplier for Apple's iPhone and iPad tablet as well as Amazon.com's Kindle tablets.

As head of LG's TV business, Han, also a 30-year veteran in displays and chip industry, helped the firm win a TV screen supply deal with Japan's Sony Corp a year ago, a major breakthrough after Sony switched to Samsung years ago for flat screen purchases.

Shares of LG Display closed down 2.7 percent prior to the announcement.

The stock has fallen around 35 percent so far this year, lagging a 7 percent drop in the broader market.

(Reporting by Miyoung Kim; Editing by Chris Lewis and Jacqueline Wong)