Foreign Minister Micheline Calmy-Rey has called on Iranian authorities to show restraint in the use of force against peaceful demonstrators.
Speaking to journalists in Bern on Tuesday she said freedom of expression must be maintained and urged Tehran to check complaints about alleged irregularities in the June 12 presidential elections.
The minister said Switzerland had been in contact with the Iranian authorities via diplomatic channels, but had refrained from making public statements until now.
"We don't want to endanger the opposition. Also we must keep open dialogue with Iran since we represent Washington's interests in Tehran," she explained.
She added that the Swiss ambassador to Tehran, Livia Leu Agosti, was in contact with the Iranian foreign ministry and kept the Swiss government informed about developments in Iran.
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