Munich security conference hears that US is ‘not powerful enough to go it alone’

The German chancellor’s speech opened the annual gathering of top global security figures including many European leaders and the US secretary of state, Marco Rubio.

The US acting alone has reached the limits of its power and may already have lost its role as global leader, the German chancellor has warned at the opening of the Munich security conference.

Friedrich Merz, the German chancellor, warned Donald Trump that the US should be wary of going solo.