LONDON, Jan 22 (Reuters) - The Swiss franc fell as much as half a percent on Wednesday after data this week indicated the country's central bank had stepped up its intervention in the market to stop its currency from appreciating.
The euro firmed as much as 0.5% to 1.0788 Swiss francs , while the dollar gained 0.4% to 0.9729 francs .
The SNB regularly intervenes to protect its export-reliant economy but last week the currency rocketed to a near three-year high against the euro after the United States Treasury added Switzerland to a watchlist of currency manipulators. Some said the move could discourage the central bank from further interventions.
But the amount of cash that domestic commercial banks hold with the Swiss National Bank (SNB) - an indication of central bank intervention - rose last week, data showed on Monday. (Reporting by Tommy Reggiori Wilkes)