Angela Merkel phone row: Germany summons US ambassador
24 October 2013 Last updated at 22:40 BST
Germany has taken the unprecedented step of summoning the American ambassador to the capital Berlin to discuss allegations that US security services monitored Chancellor Angela Merkel's phone.
The US has insisted her phone is not being monitored now but has not said what may have happened in the past.
Mrs Merkel has demanded a "complete explanation" of the claims.
Gavin Hewitt reports.