(CNN) — President Donald Trump, facing the gravest test of his presidency to date, struck a somber tone Wednesday, announcing no Americans were harmed in Iran’s retaliatory attacks against Iraqi bases housing US troops. During a White House statement, Trump also signaled a de-escalation of tensions, stating: “Iran appears to be standing down. “”We suffered no casualties. All of our soldiers are safe and only minimal damage was sustained,” Trump said. No American or Iraqi lives were lost, according to Trump, adding that an early warning system worked well.