Image caption Banks around the world could be affected by the Swiss probe

Switzerland's financial regulator is investigating possible manipulation of foreign exchange rates at several Swiss financial institutions.

The regulator, FINMA, said several banks, including some from outside Switzerland, could be implicated.

It is coordinating the investigation closely with authorities in other countries.

It would give no further details on the investigations or the banks potentially involved.

Swiss Banking, the group that represents the nation's banks, said it had no further information.

The Swiss announcement follows reports in June that the British regulator, the Financial Conduct Authority (FCA), was looking into whether traders manipulated benchmark foreign-exchange rates to increase profits.

This followed an investigation by Bloomberg News that found that dealers shared information and used client orders to move the rates.

The FCA, which does not announce its investigations, only its enforcement actions, said: "We are aware of the allegations and we have been speaking to relevant parties."

London is by far the world's biggest market for foreign currency trading, with 41% of global turnover, according to the Bank for International Settlements.

New York has a 19% share, followed by Singapore, Tokyo and Hong Kong.

Switzerland accounts for 3.2% of foreign exchange trading.