The President allowed the National Security Agency (NSA) to continue spying on   the German chancellor, it was claimed.

Mr Obama was told of the secret monitoring of Mrs Merkel by General Keith   Alexander, the head of the NSA, in 2010, according to Bild am Sonntag, a   German newspaper.

“Obama did not stop the action at that time but allowed it to continue,” a US   intelligence source close to the NSA operation told the Sunday newspaper.

The White House later commissioned an extensive NSA dossier about Mrs Merkel,   according to Bild.

The new disclosure came after it was reported that US intelligence operates a   global network of 80 electronic listening posts, including 19 in European   cities, notably Paris, Berlin, Rome and Madrid, according to Spiegel, the   German magazine.

It   also claimed that America began monitoring Mrs Merkel as long ago as 2002,   three years before she became Chancellor when she was still leader of the   opposition.

The latest twists in the US spying scandal come after President Obama   reportedly assured Mrs Merkel during a telephone conversation last week that   he was unaware the NSA had been spying on her.

In fact, the NSA monitoring of the chancellor included the content of her SMS   messages, as well as telephone calls, according to Bild.

Only her secure office landline used for communicating with other heads of   state was unaffected.

Information about Mrs Merkel was collated in the US Embassy beside the   Brandenburg Gate in Berlin and sent directly to the White House.

Her predecessor as German chancellor, Gerhard Schroeder, was also the target   of secret US monitoring following his opposition to the Iraq war, Bild says.

The   revelations about US spying on Mrs Merkel have sparked outrage   across the German political spectrum.

Three quarters of Germans now believe President Obama should issue a personal   apology to their leader, according to a poll. Meanwhile, 60 per cent of   Germans say the eavesdropping affair strongly or very strongly damages   US-German relations.

The spying row prompted leaders meeting at a European Council summit to demand   a new deal with Washington on intelligence-gathering.

Meanwhile, Michael Morrell, the former CIA deputy director, told CBS’ 60   Minutes programme that the leaks by Edward Snowden, a former NSA contractor,   have undermined American efforts to track terrorist threats.

“What Edward Snowden did has put Americans at greater risk because   terrorists learn from leaks, and they will be more careful, and we will not   get the intelligence we would have gotten otherwise,” he said.

Mr Morrell said that Mr Snowden was a traitor to his country. “I think this is   the most serious leak – the most serious compromise of classified   information in the history of the US intelligence community,” he said.