Construction on the Russia-backed nuclear plant at Rooppur began in 2017 during the iron-fisted tenure of former premier Sheikh Hasina, whose family has been accused of taking kickbacks from the deal.

The much-delayed 2,400-megawatt project is aimed at bolstering an overstretched energy grid and will be Bangladesh's largest power station by generating capacity once fully operational.

A delegation from the International Atomic Energy Agency (IAEA) was onsite Monday to conduct a pre-operational safety review of the plant, project director Md. Zahedul Hassan told AFP.

"The team will inspect all the safety issues of the plant's structural, technical and equipment-related preparation and documentation as per the IAEA's safety standards," he said.

Hassan said a further, final safety review would be held two to three months before the loading of nuclear fuel into the plant's twin reactors, expected in the middle of this year.

Transmission lines needed to connect the plant to the national grid are expected to be finished by the end of this month, he added.

The Rooppur plant was the most expensive infrastructure project undertaken by Hasina -- a $12.65 billion project, 90 percent funded by a loan from Moscow.

After Hasina's ouster in a student-led revolution last year, the interim government that replaced her launched a probe into the project's finances.

Hasina and her family are accused of embezzling $5 billion from the project, according to Bangladesh's anti-corruption commission.

Also named in the investigation was Hasina's niece Tulip Siddiq, a former British government minister who resigned in January after the Rooppur probe was announced.

She has consistently denied any wrongdoing.