China on Friday called on the international community to speed up the formulation of guidelines for cyberspace after the United States was accused of spying on the phone records of its allies.

"We have noticed relevant reports and the remarks by some nations' leaders. It is the latest testimony that cyber security is a common focus of all countries," Foreign Ministry spokeswoman Hua Chunying said at a daily news briefing.

The international community must accelerate the formulation of guidelines for a code of conduct in cyberspace within the UN framework in order to ensure an open, secure cyberspace, Hua said.

The US National Security Agency allegedly accessed millions of French phone records and tapped German Chancellor Angela Merkel's private mobile phone, according to media reports.

On Wednesday, Berlin voiced its anger at the possible US spying on Merkel, saying it would be "a serious breach of trust" if confirmed.

French President Francois Hollande on Monday expressed his "strong condemnation" of the monitoring during a phone call with US President Barack Obama, branding it "unacceptable" between friends and allies, according to the French Presidency Elysee.