Shalom, speaking to Israeli radio from London, said that the recent Iranian election results showed that hopes the Islamic republic was on the path to reform were wide of the mark.
"Iran is still a dictatorship which is trying to acquire weapons of mass destruction and that is why the world must continue to prevent its efforts to arm itself," Shalom said.
"The elections in Iraq have proved again that those who believe this country is on the path of reform and change are mistaken," he added
The reformist movement in Iran was trounced in February 20 parliamentary elections earlier most of their ranks were disqualified from standing by the Guardians Council, an unelected hardline political watchdog.
Israel has identified the regime in Tehran as its number one threat since the US-led ouster of Iraqi dictator Saddam Hussein last April.
Meir Dagan, head of Israel's Mossad overseas intelligence service, recently told lawmakers that Iran posed the biggest threat to the existence of the Jewish state since its creation in 1948.
Iran, which agreed in December to cooperate fully with the International Atomic Energy Agency in monitoring a nuclear programme it says is entirely peaceful, has threatened to use all means at its disposal including medium-range Shahab-3 missiles if Israel strikes its nuclear facilities.
Shalom said that the governments of Britain, France and Germany had come to recognise the threat now posed by Israel's alleged nuclear weapons programme.
"Berlin, London and Paris are within their range," Shalom added.
Shalom arrived in London Sunday after a trip to neighbouring Ireland which is the current holder of the rotating European Union presidency.
He is expected to hold talks at Downing Street with British Prime Minister Tony Blair as well as his counterpart Jack Straw.