The Council's move follows a unanimous United Nations Security Council resolution in December, after Tehran refused to cooperate fully with the UN atomic energy watchdog or to suspend uranium enrichment.

The Swiss ban also covers exports of plutonium and uranium as well as financial grants and investments linked to Iran's programmes.

Assets belonging to 12 Iranian citizens, and 10 Iranian companies linked to the nuclear and missile programmes, have also been frozen.

The move comes as the European Union has voiced concern over the effectiveness of the sanctions in thwarting Tehran's nuclear ambitions.

In a document obtained by AFP on Tuesday, EU officials expressed concern that international sanctions might not be enough to prevent Tehran acquiring the bomb.

"At some stage we must expect that Iran will acquire the capacity to enrich uranium on the scale for a weapons programme," the document said.

Last week, Swiss banks defended dealings with Iranian companies or individuals engaged in legitimate commercial activities, despite growing financial pressure on Tehran from the United States.

"It is difficult to put one country and its citizens in the same boat ... some people from Iran have very legitimate interests in Europe and are very trustworthy," said Pierre Mirabaud, head of the Swiss Bankers Association.