"Iran is fast apporaching the point of no return in its efforts to acquire nuclear weapons capability," Shalom said here after talks with European Union foreign policy chief Javier Solana who was fresh from a visit to Tehran.
"It's urgent that the international community act to ensure that this nightmare scenario is prevented."
Solana said he had urged the Islamic republic to agree to snap inspections by the United Nations' International Atomic Energy Agency (IAEA) in talks with Iranian Foreign Minister Kamal Kharazi on Saturday.
"We have asked the Iranian government to sign the additional protocol as soon as poosible and to give a clear and urgent anser to the question before the publication on September 8 of the report of the IAEA in Vienna," said Solana.
The European Union has joined the wider international community in pressing Iran to sign an additional protocol to the nuclear Non-Proliferation Treaty that would allow IAEA inspectors to descend on its nuclear sites without warning to ensure that Tehran was not secretly developing atomic weapons.
Brussels last month warned that, without credible guarantees over the protocol, it would review its economic ties with the country after an IAEA report on Iran is presented in Vienna between September 8 and 11.
Israel has come to regard Iran as its chief military threat since the downfall of Saddam Hussein's regime in Iraq.
It warned last month said that a new ballistic missile that was officially inaugurated by Iran's supreme leader Ayatollah Ali Khamenei represented a threat to the whole of the Middle East.