PARIS, Nov 26 (Reuters) - French waste and water management group Veolia believes it will win EU antitrust approval for its tie-up with rival Suez on Dec. 14 after the two companies offered additional asset sales to address competition concerns, two sources said.

The new concessions, which were submitted to the EU this week, are limited in scope and do not undermine the logic of the merger between the two French rivals, the sources said.

"Veolia is very confident that it will get the commission's approval on Dec. 14," one of the sources said, adding that once the green light is given, Veolia will be able to complete its takeover bid for Suez.

The two groups, who announced their planned tie-up worth nearly 13 billion euros ($14.7 billion) last April after a lengthy row, have already announced they would spin off Suez's French water and waste activities and some international assets into a new entity called "New Suez."

On top of that, the sale of some Veolia small industrial water treatment assets and mobile units to assist customers as well as Suez's assets in the field of industrial hazardous waste treatment have also been offered to the EU, the sources said.

In a statement issued on Wednesday, the European Commission said both companies had offered remedies in a bid to secure its approval, without giving details, and extended the deadline for its decision to Dec. 14.

Veolia and the European Commission declined to comment on Friday. ($1 = 0.8861 euros) (Reporting by Gwénaëlle Barzic, additional reporting by Foo Yun Chee in Brussels, writing by Lucinda Langlands-Perry, Editing by Louise Heavens)