PARIS, Sept 13 (Reuters) - Veolia's offer to acquire a stake in fellow French waste and water management group Suez will not lead to job losses at Suez, Veolia's CEO told newspaper Les Echos as he tries to overcome Suez's opposition to his plan.

Veolia offered on Aug. 30 to buy a 29.9% stake in Suez from French gas and power utility Engie for 2.9 billion euros ($3.4 billion), and, if successful, to then launch a full takeover bid to create a "world champion of ecological transformation."

The offer has been rejected by Suez, with its chairman saying in an interview published earlier on Sunday it represented an "industrial mirage" that would bring job cuts in France.

In his interview with Les Echos, Antoine Frerot said infrastructure fund Meridiam to which Veolia proposes to sell Suez's French water business has provided guarantees about preserving jobs, while employment would be the most important criteria in any sale of waste assets due to competition issues.

"For staff, there is therefore strictly no risk of job losses," Frerot was quoted as saying.

Four or five of a dozen-strong executive committee in the combined company were expected to be former Suez staff, including potentially Suez Chief Executive Bertrand Camus, he said.

Suez has said it is working on an alternative solution for Engie's stake, while Engie has said Veolia's offer is too low.

French Finance Minister Bruno Le Maire has said he would meet soon with Suez to discuss the issue.

Veolia did not plan to extend its offer beyond a current Sept. 30 deadline, Frerot said.

He reiterated that his group planned to pay for the 29.9% stake in Suez in cash, and would consider several debt options to finance a full takeover, adding Veolia had the backing of its banks.

A capital increase was another possibility but would only represent a small part of the deal financing and occur at the end of the process, he said. (Reporting by Gus Trompiz, Editing by William Maclean and Daniel Wallis)