KIEV, May 18 - The approval from the European Union may be required if Russia and Ukraine decide to go ahead with merging assets of Gazprom and Naftogaz Ukrayiny, a senior Ukrainian official said.

Andriy Honcharuk, a deputy chief of staff at the administration of President Viktor Yanukovych, said the approval was needed as most of Russian gas shipped through Ukraine is consumed in Europe.

“There are quite serious arguments among experts that the approval of the European Commission is needed for the merger,” Honcharuk said in an interview with Channel 5 late Monday.