Technical issues are to delay the start-up of Iran’s first nuclear power reactor, Russian authorities in charge of the project have announced.

Russia’s energy minister Sergei Shmatko said politics played no role in the decision to delay the launch of the power plant, which was expected to go online by the end of the year, reports Reuters.

“The engineers have to reach their findings,” he said. “The building of the Bushehr station is defined absolutely 100% by technological conditions,” Shmatko is quoted by Reuters as saying.

In 1995, Russia agreed to build the $1bn nuclear plant in southwest Iran and in late 2007 Russia began nuclear fuel deliveries for Bushehr.