President Donald Trump has stood by claims he was wiretapped under Barack Obama, telling visiting German Chancellor Angela Merkel: "At least we have something in common, perhaps."
US intelligence agencies under Mr Obama reportedly monitored Mrs Merkel's phone, sparking an angry response, BBC reports.
But both Republican and Democratic congressional leaders have said they do not believe Mr Trump was wiretapped.
Trump and Merkel have discussed key issues including Nato and trade.