TEHRAN (Reuters) — Iran’s first nuclear power plant has finally begun to provide electricity to the national grid, official news media reported on Sunday, a long-delayed milestone in the nuclear ambitions of a country the West fears is covertly trying to develop atomic weapons.

The start-up will come as a relief to Tehran after many years of delays and false starts at the plant it hopes will show the world it has joined the nuclear club, despite sanctions imposed in an effort to curb its nuclear progress.

The $1 billion, 1,000-megawatt Bushehr plant will be formally inaugurated Sept. 12, by which time it will be operating at 40 percent capacity, Hamid Khadem Qaemi, spokesman for the Atomic Energy Organization of Iran, told the state-controlled Arabic-language TV station Al Alam.