The UN's top nuclear official says the world's reliance on atomic power will continue to grow, despite the crisis at Japan's Fukushima plant.
Mr Amano visited the Fukushima plant on Monday for the first time since it was crippled by the earthquake and tsunami.
He said he supported Tokyo's plan to shut the plant by January.
Since the 11 March disaster caused partial meltdowns at three of Fukushima's reactors, a global debate has raged about the future of nuclear power.
Germany has announced plans to abandon nuclear entirely, and Japanese Prime Minister Naoto Kan has floated the idea of a nuclear-free Japan.
PM under pressure
After meeting Mr Kan on Tuesday, Mr Amano told reporters: "It is certain that the number of nuclear reactors will increase, even if not as quickly as before.
"Some countries, including Germany, have reviewed their nuclear energy policy, but many other countries believe they need nuclear reactors to tackle problems such as global warming. Therefore, securing safety is more important than anything."
IAEA officials said they expected the world's reliance on nuclear power to grow because China and India were pressing on with their power programmes.
In 2009, there were 12 nuclear plants under construction, 11 of which were in China, the IAEA said.
In Japan, the earthquake and tsunami knocked out the cooling facilities at the Fukushima plant, eventually causing explosions and leaks of radioactive material.
Thousands of people were evacuated from their homes around the plant.
Within the past week, Japanese officials say they have now achieved stable cooling in the reactors and claim to be on course for a "cold shutdown" by January.
No-one has died as a result of the nuclear crisis, but the quake and tsunami flattened towns and villages along Japan's north-eastern coast, killing more than 15,000 people.
Japan is struggling to recover from the disaster, with the prime minister under constant pressure to resign, hampering his attempts to organise recovery efforts.