The Swiss government regrets the “deteriorating” situation regarding sanctions imposed by the US on Iran, but recommends Swiss firms pursue their business relations with Tehran on an informed basis, it said on Thursday. Companies doing business with Iran will be barred from the US, President Donald Trump said on Tuesday, as new US sanctions took effect despite pleas from Washington’s allies. “US decisions on sanctions do not affect the legal situation in Switzerland with regard to Iran,” said Fabian Maienfisch of the State Secretariat for Economic Affairs (SECO). However, renewed US sanctions may affect Swiss firms that have business relations with Iran, Reuters said. The Swiss federal government will defend Swiss economic interests but cannot dictate the reaction of companies to the new climate, the official said.