Belarus has successfully launched the first chain reaction at Unit 1 of the Astravets nuclear power plant.
"This marked the beginning of the reactor's life cycle," the Energy Ministry said on its Telegram channel on October 11.
Built by Russian state firm Rosatom and financed by Moscow with a $10 billion loan, the Astravets nuclear power plant project is opposed by neighboring EU members Lithuania and Latvia because of its proximity to the border.
When fully operational in 2022, the nuclear plant's two VVER-1200 type reactors will produce up to 2,400 MW of electricity.
The Energy Ministry said in its latest update that a fission chain reaction at one of two reactors was brought to a minimum controlled level. The reactor will undergo several tests to confirm safety and reliability.
The next stage will be to start energy production and include the unit in the country's energy system.
On October 13, the director of the Department for Energy Efficiency, Mikhail Malashenka, said that the commissioning of the nuclear power plant will allow Belarus to minimize its dependency on gas and oil imports.
Lithuania, Latvia, and Estonia are moving to a full decoupling from their Soviet-era common power system by 2025 as part of an EU goal to better integrate the bloc's electricity grid.
Lithuania has already banned all electricity imports from the Astravets plant, citing concerns about safety and national security.
Belarus has rejected suggestions that the plant poses a risk and has insisted it meets all safety standards.