Belarus’ first nuclear power plant began operating Tuesday, a project that has caused jitters in neighboring Lithuania, which immediately cut off electricity imports from the Belarusian plant.

The Russian-built Ostrovets nuclear power station, 40 kilometers south of the Lithuanian capital of Vilnius, has been connected to Belarus’ power grid and has started producing electricity, according to Belarusian electricity operator Belenergo in comments carried by the state news agency BelTA.

Lithuanian authorities long have opposed the plant’s construction, arguing that the $11 billion project has been plagued by accidents, stolen materials and the mistreatment of workers. In keeping with the Vilnius’ new law banning electricity imports from Belarus once the plant starts, Lithuania’s Litgrid power operator cut the inflow of electricity from Belarus upon receiving data that the Belarusian nuclear reactor had started producing energy, the Associated Press reported.

Neighboring Latvia said it had also blocked imports of energy generated at the plant and vowed not to purchase Russian electricity if Moscow was unable to prove imports did not originate from the Belarusian plant.

Russia’s state nuclear corporation Rosatom, which built the plant, has rejected the Lithuanian complaints, saying the plant’s design conforms to the highest international standards as confirmed by the International Atomic Energy Agency, a U.N. watchdog.

The corporation also insisted that it “has a zero-tolerance policy on corruption” and that it maintains “an internal control system that ensures that any illegal or inappropriate practices are stopped and prosecuted.” It argued that the project’s launch would help reduce the region’s carbon emissions by up to 10 million tons of CO2 equivalent every year.

“We are working closely with Belarus’s national nuclear regulator, the World Association of Nuclear Operators, and with the EU’s European Nuclear Safety Regulators Group to make absolutely certain that there are no unaddressed risks or ‘threats to safety,’” Rosatom said in a statement issued to The Associated Press.

The Ostrovets project has proved divisive within the Belarus, which suffered severe damage from the 1986 Chernobyl nuclear disaster, which spewed radioactive fallout from Ukraine to Europe.

Lithuania’s Foreign Minister Linas Linkevicius said Belarus had commissioned the plant despite despite “unresolved safety issues,” and described the project as a “geopolitical” move by Moscow to spread political influence.

“The EU as the whole international community simply cannot stay indifferent to such cynical ignorance,” he said on Twitter, according to Radio Free Europe.

The nuclear plant’s construction was delayed in 2015 when a crane operator dropped a 330-ton reactor pressure vessel, a sensitive structure that houses the reactor core, from a height of four meters. Officials sought to cover the incident up, but it was eventually brought to light by a whistleblower. At the time, Rosatom insisted that the reactor wasn’t damaged, but it agreed to replace the unit at the demand of Belarusian authorities.

Another reactor pressure vessel bound for the plant was accidentally run into a cement column when it was being unloaded from a rail car.

In recent weeks, Lithuanian authorities have handed out free iodine pills to residents living near the Belarus border. Iodine can help reduce radiation build-up in the thyroid in case of a leak of radioactivity.

Last month, Lithuania, Latvia and Estonia announced plans to band together to in their refusal of electricity imports from the Belarusian plant, as well as to improve their bargaining position with other energy vendors. The agreement is expected to cut energy trading among the Baltic states by half. The agreement will remain in force until the Baltic electricity systems are synchronized in late 2025.

When fully operational in 2022, the nuclear plant’s two reactors are expected to produce up to 2,400 megawatts of electricity.