Electronics rivals Sony Corp. and Sharp Corp. are teaming up to make flat panels for LCD TVs.

The companies said it’s undecided how much they’ll spend on their joint venture, but The Nikkei business newspaper reported Sony will invest $926 million in a plant Sharp is building. The venture will control the plant, which is under construction and expected to be running by March 2010.

Sony, which doesn’t produce panels, has been buying LCD panels from another venture it has with Samsung Electronics Co. of South Korea, and Sony said Tuesday that its deal with Samsung will continue unchanged.

With the Sharp partnership, Sony is looking to ensure a stable supply for its TVs. The joint venture will be set up by April 2009, with Sharp taking a 66 percent stake and Sony 34 percent, the companies said.

“Ensuring a stable procurement of panels is critical,” Sony President Ryoji Chubachi said at a news conference with Sharp President Mikio Katayama. “This is an important step in Sony’s effort to become the world’s No. 1 TV maker.”

Osaka-based Sharp, which is struggling to gain overseas brand recognition, still trails Samsung and Sony.

Analysts said the joint venture was positive for both companies, as it would give Sony more of an option in buying panels for its Bravia TVs, while Sharp can reduce the investment burden for panel production.

Katayama acknowledged that Sharp and Sony will be competing intensely as TV makers, but he added they will also be able to cut costs and increase scale of production through the joint venture.

“This will strengthen the LCD business in Japan,” he said. “We will do our utmost aiming to become the world’s No. 1.”

Demand for slimmer and bigger TVs is growing around the world. Although the televisions use various panel technologies, LCD is the leading technology so far along with plasma display panels.

Sony management failed to recognize how quickly slimmer TVs would take off, partly because of the huge success it had enjoyed in developing and selling high-quality old-style televisions.

Its failure in flat TVs was a major reason for its faltering earnings several years ago. Sony has staged a comeback recently under the leadership of Howard Stringer, a Welsh-born American who became chief executive in 2005.