By Gus Trompiz and Sybille de La Hamaide

PARIS, March 21 (Reuters) - Financial markets operator CME Group CME.O is working on plans for a Black Sea wheat futures contract tracking Romanian and Bulgarian prices, European traders said.

CME, which has U.S. corn, wheat and soybean futures that act as global price benchmarks, suspended trading in its previous Black Sea wheat futures based on a Russian price index following the full-scale invasion of Ukraine.

While Russia and Ukraine are much larger wheat suppliers, the export role of European Union members Romania and Bulgaria has expanded in recent years.

The new product would be linked to an index of export prices for 12.5% protein wheat in the "CVB" zone that comprises the Romanian port of Constanta and the Bulgarian ports of Varna and Burgas, traders said.

A draft document seen by Reuters showed that the futures would be cash-settled, rather than physically deliverable, priced in U.S. dollars and traded in 50 metric ton lots.

Traders, citing CME consultations, said the expectation was that the product could be launched in time for trading this summer's harvest.

However, it was not known if CME had decided to proceed or if proposed contract specifications could be modified, they added.

"We are always talking to our clients and the industry about risk management needs, but can't comment on whether or not we are developing any particular product," a CME spokesperson said.

Like rival Euronext ENX.PA, CME has been exploring how to develop in the Black Sea region for years, with traders saying it has been considering options including Romania since the war in Ukraine.

On top of good harvests and competitive prices, war-related risks affecting Russian and Ukrainian supplies and a dire harvest last year in top EU producer France have increased buyer interest for Romanian and Bulgarian wheat.

At the same time, U.S.-led efforts to negotiate a ceasefire have raised the prospect that market conditions may stabilise again in Russia and Ukraine.

CME has unveiled several new grain products in recent months, including U.S. spring wheat futures due to launch next month and contracts for trading price spreads between CME and Euronext futures that launched in October.

(Reporting by Gus Trompiz and Sybille de La Hamaide; Editing by Kirsten Donovan)

((gus.trompiz@thomsonreuters.com;))