Merkel outraged after NSA allegedly tapped her phone

Earlier that day, Spiegel Online reported that the National Security Agency had tapped her phone, as part of its large-scale spying operations abroad, revealed by fugitive whistleblower Edward Snowden.

The White House said President Obama sought to reassure the German leader that there is no current monitoring of her communications.

"I can tell you that the president assured the chancellor that the United States is not monitoring and will not monitor the communications of the chancellor," Jay Carney, the White House spokesman, said during a press conference.

He could not confirm, however, that the NSA has not intercepted Merkel's phone calls and text messages in the past.

Merkel sought to avoid a diplomatic scandal with the US over the NSA spying affair in the run-up to her re-election in September, despite revelations that Germans' communications are being snooped.

During a visit to Berlin in summer, Obama tried to reassure Merkel and German citizens that there are no illegal spying activities and that all leads are shared with EU partners in the fight against terrorism.

But more details have emerged since, including the cooperation of the German intelligence services with the NSA in this large surveillance of online communications.

France meanwhile also has been exposed as a target of the NSA's surveillance, with the US intelligence agency reportedly sweeping up to 70.3 million telephone records in one month, Le Monde reported

"Why are these practices, as they're reported – which remains to be clarified – unacceptable? First because they are taking place between partners, between allies, and then because they clearly are an affront to private life," French government spokeswoman Najat Vallaud-Belkacem said Wednesday.

In Italy a similar scandal is brewing after media reports that members of a parliamentary committee were told during a visit to Washington that phone calls, emails and text messages of Italians had been intercepted.

Prime Minister Enrico Letta raised the surveillance issue during a meeting on Wednesday with US secretary of state John Kerry.

MEPs call for halt to bank data deal

Meanwhile, the European Parliament on Wednesday became the first EU institution to take a stance against the spying scandal.

In a non-binding vote, a majority of MEPs asked for an EU-US agreement on transferring banking data to be suspended due to the NSA scandal.

The agreement can only be halted if two thirds of member states agree.

But MEPs also said they may withhold their consent to future international agreements if the EU response to the NSA scandal is not satisfactory.

The EU commission earlier this summer started negotiations on an EU-US free trade agreement, one such deal that could be affected by the political fallout of the spying scandal.