The transaction is expected to be completed in the first quarter of 2024, upon the fulfillment of certain conditions, including clearance from regulatory bodies, OMV Petrom said in a press release.
OMV Petrom did not disclose the value of the transaction.
Biofuels should account for more than 15% of the group's output by 2030, according to its strategy.
"Through this transaction, we take a first step towards ensuring our access to the raw material necessary to produce biofuels and open up the prospect of integrating the circular economy into our core activities," Radu Caprau, member of OMV Petrom's executive board, was quoted as saying.
Established 12 years ago, Respira Verde collects up to 10,000 tonnes of used cooking oil per year from companies active in hospitality and retail. The company owns its own transport fleet and two warehouses in Bihor and Ialomita.
Austria's OMV Aktiengesellschaft holds a 51.157% stake in OMV Petrom. The Romanian economy ministry owns 20.698% and 28.145% is free float on the Bucharest bourse and the London Stock Exchange.
Shares in blue-chip OMV Petrom traded 0.36% higher at 0.554 lei ($0.12/0.11 euro) by 1336 CET on Thursday on the Bucharest bourse.
(1 euro=4.97021 lei)