The plant in northern Poland will cost an estimated $23 billion to build, with the first reactor set to come online in 2033.

Poland was among 11 EU nations that agreed last February to deepen cooperation on nuclear energy, calling it the best strategy to meet goals on cutting carbon emissions.

While Warsaw's plans to pursue nuclear power have been in the works for years, Russia's invasion of Ukraine and the subsequent turbulence on global oil and gas prices have given the project new urgency.

But the issue has divided Europe and several EU states are fiercely opposed to further nuclear plants on the continent, with Germany and Spain leading the criticism and saying the focus should be on developing renewable sources.

"Today, Poland opens a new chapter in nuclear energy. Just as the 20th century belonged to coal and oil, the 21st century belongs to the atom," Prime Minister Mateusz Morawiecki said at a contract signing ceremony.

"We cannot risk the stability of our energy system, the stability of our entire economy, by relying on unstable energy sources," he said.

Poland plans to eventually have three nuclear power plants, each with three reactors, generating around 30 percent of its energy production.