Earth excavation will initially go down to five meters below ground level, the same depth as for the planned block five. Szijjártó noted that, meanwhile, construction of a slurry wall is progressing, and reactor tank production is also underway in Russia.

"All this means that the completion of the works in 2030 is still a realistic goal," Szijjártó said.

Russia's Rosatom is the general contractor for building the two new blocks at the Paks plant. The existing four blocks account for about half of Hungary's domestic electricity generation.

With the completion of Paks II, Hungary's nuclear energy capacity will climb from 2,000 MW to 4,400 MW.