The value of uncut diamonds traded in Switzerland has collapsed, following the decision by the world's largest gem firm De Beers to relocate to London.
Last year, SFr2 billion ($1.4 billion) worth of uncut diamonds was traded in Switzerland - in the first seven months of this year, that figure had fallen to SFr7 million.
Roland Vock of the State Secretariat for Economic Affairs said until last year, Switzerland was the third most important diamond trading centre after London and Antwerp.
Vock said the most likely reason for the slump was the decision of the world's largest diamond company, De Beers, to move its headquarters away from the central Swiss city of Lucerne to London.
In 2000, Switzerland came under fire by the United Nations for allegedly being a major transit country for so-called blood diamonds.
These diamonds were coming into Switzerland from war-torn Angola and Sierra Leone and being declared Swiss.
This meant that they were bypassing a UN boycott on diamonds used to fund conflicts.
The Swiss authorities responded by imposing tight controls on the movement of diamonds at customs points in Zurich and Geneva.
At the time of its relocation, De Beers told swissinfo the move had nothing to do with Switzerland’s tougher regime on the import and export of gems.
Switzerland is also taking part in the Kimberley Process, which aims to track the origins of diamonds and clamp down on illicit trading.