In a statement on nuclear non-proliferation, the G8 group of leaders said they were "seriously concerned" about the implications of Iran’s advanced nuclear programme.
They said they fully supported a decision by foreign ministers of the five permanent Security Council members plus Germany last week to return the issue to the world body.
That decision came after Iran failed to suspend uranium enrichment, which can produce nuclear fuel or material for atomic weapons, to allow negotiations to begin on resolving the crisis.
"We … fully support this decision and the clear messages it sends to Iran about the choice it must make," the G8 statement said.