The US Nuclear Regulatory Commission has approved a series of licensing and regulatory actions that will allow fuel loading at Holtec's plant.
The US regulator has renewed the operating licence for VC Summer unit 1 for a second time, clearing the pressurised water reactor to operate until August 2062.
Russia's nuclear regulator Rostekhnadzor has issued an operating licence to the Kalinin nuclear power plant's unit 1 to June 2044.
Unit 1 at the plant could restart as early as 2027 with the approval of an early interconnection request by grid operator PJM, Constellation said as it held a celebration of progress at the plant in Pennsylvania.