In a new report the International Atomic Energy Agency (IAEA) said that the sector would face challenges as "ageing reactors are retired and the industry struggles with reduced competitiveness".

"Overall, the new projections suggest that nuclear power may struggle to maintain its current place in the world's energy mix," the IAEA said.

In its worst case scenario, nuclear power capacity would fall by more than 10 percent until 2030.

Other factors cited as contributing to the squeeze on the sector were the low price of natural gas, the impact of renewable energy sources on electricity prices and the global reaction to the 2011 Fukushima disaster in Japan.

Several countries have announced plans to phase out nuclear power, including Germany and Switzerland, and the IAEA says the industry "faces increased construction times and costs due to heightened safety requirements".

Given this, and "the considerable number of reactors scheduled to be retired around 2030 and beyond", the lower end of the IAEA's projections see capacity falling by more than 10 percent from its 2017 level of 392 gigawatts.

Capacity in Europe and North America could fall by almost a third under that same scenario.

On a global level, that projection would see nuclear power declining to 2.8 percent of world electricity generation by 2050, down from 5.7 percent today.

"Still, interest in nuclear power remains strong in the developing world, particularly in Asia where countries such as China and India need huge amounts of electricity and also want to reduce greenhouse gas emissions," the IAEA notes.

"Without significant progress on using the full potential of nuclear power, it will be difficult for the world to secure sufficient energy to achieve sustainable development and to mitigate climate change," IAEA Director General Yukiya Amano said.

However, green campaigners often point to the potential hazards of nuclear waste and say that investment in renewable energy is a more sustainable route to combatting climate change.