Guido Westerwelle
Guido Westerwelle Reuters

German Foreign Minister Guido Westerwelle said Thursday that the international community will block Iran from obtaining a nuclear weapon.

"The current Iranian nuclear program represents an enormous danger, not only to Israel but to the region as a whole," Westerwelle told Jewish Global Forum in Washington.

"We cannot and will not accept an Iranian nuclear weapon... We need substantive and verifiable guarantees that Iran is not pursuing a nuclear weapon."

Israel, Washington, the European powers, and Gulf Arab states are concerned Tehran is trying to develop atomic weapons under the cover of a civilian nuclear program. Iran insists its nuclear program is purely peaceful.

However, in early March, the head of the International Atomic Energy Agency said there were indications that Iran was engaged in nuclear weapons research.

"Iran is not telling us everything. That is my impression. We are asking Iran to engage with us proactively, and Iran has a case to answer," said IAEA director Yukiya Amano.

His remarks followed two recent IAEA reports that indicated Iran had sought – and likely continues to seek – nuclear technologies of a military nature.

IAEA experts previously reported Iran's production of 20% enriched uranium is far greater than needed for peaceful purposes. They also note Iran's medical research sector is not sufficiently advanced to justify such production. 

Last month, the so-called P5+1 group - the five permanent members of the UN Security Council plus Germany - met in Istanbul with Iranian officials to discuss their concerns, with a further meeting set for May 23 in Baghdad.

Israeli officials say further talks are futile and charge Iran is playing for more time to develop an atomic bomb. 

However, Westerwelle called for further negotiations with Tehran, stressing that "our unity and our resolve are showing results."

At the same time, he made clear that "our patience is limited. We will not accept playing for time," adding, "the Iranian regime continues to threaten Israel with annihilation."

"I want you to know that we will continue to stand by Israel's side," he told the Jewish Global Forum.

Israeli leaders have consistently warned that a nuclear-armed Iran would pose an existential threat to the Jewish state, and that a preemptive military strike remains "on the table."