Iranian President Mahmoud Ahmadinejad said on Thursday that the United States must make its position on Israel's nuclear strategy clear before talks on Tehran's atomic program could resume.

Sanctions imposed by "arrogant" Western powers would not slow Iran's nuclear progress, he said.

Open gallery view Technicians measuring parts of Iran's Bushehr nuclear power plant in this undated photo. Credit: AP

The United States, Europe and the United Nations have imposed sanctions on Iran over its disputed nuclear program. Iran says its aim is to generate electricity and rejects Western suspicions it is seeking to build a nuclear bomb.

Iran's chief nuclear negotiator suggested in a letter to the European Union's foreign affairs chief this week that talks could be held as soon as September on issues including Tehran's atomic program.

Speaking in Nigeria after a summit of the D8 group of developing nations, Ahmadinejad said Iran supported dialogue but blamed the United States for the failure of previous talks.

Asked what conditions must be met for talks to resume, Ahmadinejad said Washington must make its position on Israel's nuclear strategy clear.

"The first condition is they should express their views about the nuclear weapons of the Zionist regime. Do they agree with that or not. If they agree that these bombs should be available to them, the course of the dialogue would be different," he said.

Israel is widely assumed to have the only nuclear arsenal in the region but it refuses to confirm or deny having such weapons. It has usually been spared scrutiny by its guardian ally but the Obama administration alarmed Israel in May by backing an Egyptian initiative for talks in 2012 on a Middle East free of weapons of mass-destruction.

However, hosting Prime Minister Benjamin Netanyahu on Tuesday, U.S. President Barack Obama echoed Israel's veiled justifications for having the bomb and said Israel had "unique security requirements".

The White House said Obama had further pledged to keep Israel, which has not signed the Non-Proliferation Treaty, from being "singled out" at a meeting of the U.N. nuclear watchdog in Vienna in September as well as at the Egyptian-proposed regional conference.

Ahmadinejad, speaking to reporters through an interpreter, said the United States must also clarify its own commitment to non-proliferation and its position on its readiness to "resort to force".

Iran is seeking closer trade ties with Africa and Ahmadinejad laced a speech to Nigerian academic, civil society and religious groups with parallels between African relations with ex-colonial powers and Iran's own standoff with the West.

"The wealth they stockpiled came from the pockets of others. They have plundered and looted all the mines in Africa. They have plundered the labor force for hundreds of years," he said.

It was a message that resonated with some of the audience at the gathering in Africa's most populous nation of 140 million people, roughly equally divided between Christians and Muslims.

"They call the leaders of America leaders of the free world. We call you the leader of nations struggling for freedom," said Shehu Sani, president of Nigeria's Civil Rights Congress.

"Dr, Ahmadinejad is a role model, he is an inspiration."

But Sani also tackled the Iranian leader about his public statements questioning whether the Nazi Holocaust in which six million Jews were killed across Europe had indeed occurred, comments which stirred tensions with Israel.

Ahmadinejad replied: "Why should they occupy the land of the Palestinian people. The people of Palestine committed no crime during World War Two."