)
The US Senate has blocked a move to put an end to the mass storage of telephone data by the National Security Agency (NSA), a measure that had the support of the White House and was a direct consequence of leaks by Edward Snowden.
The controversial reform, called the USA Freedom Act, fell short by two votes of the required 60 to move forward on the Senate floor, with all the Republican caucus against it, except four senators, including Ted Cruz from Texas.
The House of Representatives approved its own version of reform in May but failed to get enough support from privacy advocates.
A new rectified text incorporating those concerns reached the Senate this summer and obtained support from Obama and leading technology companies, as well as the American Civil Liberties Union.
If Congress, which will be under Republican control from January, does not act, a key provision of the US Patriot Act that empowers the country's intelligence to collect phone data in the fight against terrorism, faces expiry June 1.
Republican Mitch McConnell, who in January will become the Senate majority leader, is one of the legislators who emphatically opposed the reform, claiming it would put an end to one of the key methods of gathering relevant intelligence information about terrorist threats.
"This is the worst possible time to be tying our hands behind our backs," he added, referring to the Islamic State Sunni radical group's threat in Syria and Iraq and beheading of Westerners in recent months by the jihadi group.
Reform would ban the NSA from storing billions of telephone "metadata", including almost all telephone connections of Americans.
According to this norm, US telephone companies would maintain this information which would be limited to the telephone number, call duration and location for 18 months.
The NSA would have access to these data only by means of a judicial authorisation giving details of the specific purpose of tracking communications and to investigate terrorist plans orchestrated from abroad.
In the past, the NSA could request permission to take stock of these connections and store in its own database for years for intelligence analysis that sometimes exceeded the justification that motivated the initial court order.
The controversial Patriot Act, created after the Sep 11, 2001, attacks, extended the scope of NSA espionage to an unprecedented level and avoiding certain safeguards to protect the privacy of Americans preserved in the Constitution.
Snowden, a former analyst for the NSA contractor Booz Allen Hamilton, leaked details of the massive accumulation of telephone connections and espionage on the internet prompting Obama to act.
The president proposed in January to put phone data in the hands of telecommunications companies and asked Congress to legislate on the issue, which could more clearly be considered a violation of the US constitution.
