Bulgaria has granted Spain's Repsol permission to transfer 30% of the rights to explore a block off its Black Sea coastline for gas and oil to the other two rights holders.

After the transfer, a unit of French oil company Total would hold 57.14% of the rights, while a unit of Austria's OMV would have 42.86%, the Bulgarian government said in a statement [last] Wednesday.

The government extended a permit granted in 2012 for deepwater oil and gas exploration in the 1-21 Khan Asparuh block by two years until May 15, 2022. The permit was granted as part of Bulgaria's efforts to end its reliance on Russian natural gas supplies.

"During the two-year extension, additional geological and geophysical works and seismic surveys worth a total of 3.3 million euros will be carried out," the government said.