The US has irked its friends and allies due to more revelations of its intelligence snooping activities, with Germany and France uniting to push for answers from Washington over its alleged espionage.
Given the massive US spy operations, countries around the world should raise their alert levels toward US technology firms, which play dominant roles in the global information and telecommunication sectors, warned analysts.
German Chancellor Angela Merkel, whose mobile phone was revealed to have possibly been bugged by the US, will hold a meeting with French President Francois Hollande on the espionage issue ahead of a meeting of EU leaders in Brussels on Thursday, according to officials from the two countries.
Earlier on Thursday, Germany summoned the US ambassador to Berlin over the issue.
On Wednesday night, an angry Merkel called US President Barack Obama, demanding "an immediate and comprehensive explanation" from Washington over what she warned was a serious breach of trust, her spokesman said in a statement.
White House spokesman Jay Carney said Obama assured Merkel the US was "not monitoring and will not monitor" her communications, however, he didn't deny the possibility that it had happened in the past.
Following leaks by former US National Security Agency contractor Edward Snowden, which revealed the reach of the US' vast data-monitoring program, Washington finds itself at odds with a host of important allies, from Brazil to Saudi Arabia.
The latest victim is revealed to be Italy. According to a report due out on Friday by the Italian weekly L'Espresso, Britain and the US monitored Italian telecommunications networks, targeting the government and companies as well as suspected terrorist groups.
Guo Longlong, a research fellow for American studies at the Shanghai Institutes for International Studies, told the Global Times that US spying activities have crossed the line, which would damage its reputation among its allies.
Advanced technology, flaws in data protection laws and hegemony thoughts have allowed the US to take surveillance and spying activities through Internet and phones, said Qin An, director of the China Institute of Cyberspace Strategy.
Qin warned that countries, including China, should enhance awareness of data protection and watch out for US surveillance and spying activities via its high technology companies operating around the world.
According to Reuters, the accusations from European countries could encourage member states to back tough data privacy rules being drafted by the EU. The European Parliament approved this week an amended package of legislation that would overhaul EU data protection rules that date from 1995.
This would restrict how data collected in Europe by firms such as Google and Facebook is shared with non-EU countries, introduce the right of EU citizens to request that their digital traces be erased from the Internet, and impose fines of up to $138 million on rule breakers.
The US is concerned that the regulations will raise the cost of doing business and handling data in Europe. Google, Yahoo!, Microsoft and others have lobbied hard against the proposals, Reuters reported.
Agencies contributed to this story