Changes made to Romania's Petroleum Law, which would give the government discretion to potentially block Russian companies from buying oil concessions, have raised concerns for the oil and gas industry as Romania gets ready for its first licensing round in more than 10 years.

For the past year, Romania has been preparing to launch its 11th licensing round, offering 28 onshore and offshore blocks.

The National Agency for Mineral Resources of Romania (NAMR) said six offshore blocks in the Black Sea, each of between 800 and 900 square kilometres in size, and 22 onshore blocks spread across the country, will be on offer.