GENEVA - U.N. Secretary-General Antonio Guterres, commenting on Friday on the situation in the Gulf, said 'I have only one strong recommendation: nerves of steel,' U.N. spokeswoman in Geneva Alessandra Vellucci said. Iranian officials told Reuters on Friday that Tehran had received a message from U.S. President Donald Trump warning that a U.S. attack on Iran was imminent but saying he was against war and wanted talks on a range of issues. The New York Times said Trump had ordered air strikes but then called them off.