United States officials claim the White House only discovered the National Security Agency was spying on world leaders in the middle of the year and cut off some monitoring operations.
Officials told the Wall Street Journal an internal Obama Administration review turned up the spying operation on German Chancellor Angela Merkel and 34 other leaders - the first public admission the NSA tapped their phones.
Officials told the Journal some programmes had been terminated and others had yet to be phased out.
The paper said: "The account suggests President Barack Obama went nearly five years without knowing his own spies were bugging the phones of world leaders. Officials said the NSA has so many eavesdropping operations under way that it wouldn't have been practical to brief him on all of them."
An official told the Journal: "These decisions are made at NSA. The President doesn't sign off on this stuff."
Obama has launched reviews in response to the revelations about NSA spying sparked by whistleblower Edward Snowden. The Journal says Administration officials are repeatedly citing those reviews in response to anger from foreign leaders.
Earlier yesterday, the NSA denied reports that Obama was personally informed of US tapping of Merkel's phones in 2010. NSA chief General Keith Alexander "did not discuss with President Obama in 2010 an alleged foreign intelligence operation involving German Chancellor Merkel, nor has he ever discussed alleged operations involving Chancellor Merkel", spokesman Vanee Vines said. Obama was dragged into the transatlantic spying row yesterday after it was claimed he personally authorised the monitoring of Merkel's phone three years ago after he was briefed by Alexander.
The latest claim, reported in the German newspaper Bild am Sonntag, followed reports in Der Spiegel that the surveillance of Merkel's phone began as long ago as 2002, when she was still the Opposition leader, three years before being elected Chancellor. That monitoring only ended in the weeks before Obama visited Berlin in June this year, the magazine said.
Citing leaked US intelligence documents, it also reported that America conducted eavesdropping operations on the German Government from a listening post at its embassy by the Brandenburg Gate in Berlin, one of more than 80 such centres worldwide.
Last week Obama assured Merkel that her phone is not being monitored now - and will not be in future.
The surveillance operations raise questions about whether US officials breached domestic laws. Hans-Peter Friedrich, the German Interior Minister, said: "If the Americans intercepted cellphones in Germany, they broke German law on German soil."
German intelligence chiefs are travelling to Washington this week to demand answers from the NSA about the alleged surveillance of Merkel.
John Kerry, the US Secretary of State, received a dose of European fury at the weekend when he visited Paris and Rome. The trip was arranged to discuss the Middle East peace process, the Syrian civil war and Iran's nuclear programme. Instead, he was confronted by outrage over the scale of US surveillance operations.
"The magnitude of the eavesdropping is what shocked us," said Bernard Kouchner, a former French Foreign Minister, in a radio interview. "Let's be honest, we eavesdrop too. Everyone is listening to everyone else. But we don't have the same means as the US, which makes us jealous."