Getty Hollande to Obama: start explaining The French president’s office calls it “unacceptable” that French leaders and their staffs were monitored for at least six years.

PARIS — French President François Hollande reacted angrily to revelations Wednesday that the U.S. spied on him and his predecessors, issuing a demand to President Barack Obama that Washington never again spy on France.

Obama assured Hollande in a 15-minute phone call that the U.S. was holding to its 2013 vow to stop spying on the leaders of allied nations, according to a statement from French president's office.

"President Obama repeated unambiguously his firm commitment ... to put an end to practices from the past that were unacceptable between allies," the Hollande statement read.

The diplomatic row stems from revelations that the U.S. allegedly spied on presidents Jacques Chirac, Nicolas Sarkozy and Hollande as well as senior diplomatic and economic staff between 2006 and 2012, according to news organizations Mediapart and Liberation, which cited leaked documents from the U.S. National Security Agency obtained by Wikileaks.

The publications wrote, referring to NSA documents allegedly classified "top secret," that the NSA phone taps also ensnared a vast circle of officials including members of parliament, the former spokesman of the Ministry of Foreign Affairs and the former French ambassador to Washington, Pierre Vimont.

While the U.S. Congress has curtailed the powers of its spy agencies with the 2015 Freedom Act, and France is not expected to take punitive measures beyond summoning the U.S. ambassador, the revelations generated anger and resentment at an ally often viewed as untrustworthy. Politicians of all stripes urged Hollande to take a stronger stand against the United States, including by asking ambassador Jane Hartley to leave the country, or by summoning home the French envoy to the United States.

Prime Minister Manuel Valls, asked in parliament about the spying allegations, called them "unacceptable" and a grave violation of trust between the two countries.

French government spokesman Stephane Le Foll said at a press briefing that the coordinator of French intelligence agencies, Didier Le Bret, would meet with U.S. officials in coming days to assess the safeguards against mutual spying that had been agreed between the two countries.

Pierre Lellouche, a deputy from the center-right Les Républicains party, underscored the need for close intelligence cooperation between France and the U.S. but called the leaks "unacceptable."

"The Républicains expect the President of the Republic to not be satisfied with summoning the United States ambassador in Paris, but to ask his US counterpart for explanations and a public apology," Lellouche said in a statement co-signed with Philippe Meunier, another deputy.

Other politicians pressed for tougher diplomatic statements.

"The act is sufficiently serious that we should send home the ambassador," Renaud Muselier, a center-right member of European Parliament, told RFI radio. "Once they have been caught, that they have demonstrated such disloyalty, it's necessary that we punish."

That echoed a call by the National Front party's Marion Marechal Le Pen to summon home France's ambassador to the U.S.

Hollande convened his top defense advisers Wednesday to discuss the revelations, and he later sat down at the Elysee presidential palace with members of parliament.

"These are unacceptable facts that have already given rise to talks between the United States and France," Hollande's office wrote in a statement, citing presidential-level talks in 2013 and 2014. "France, which has further reinforced its control and protection systems, will tolerate no action that compromises its security and the protection of its interests."

New information about the sweeping extent of NSA spying on a country allied to the U.S. is likely to revive criticism of the Americans' posture toward its allies that first flared following the release of a first trove of NSA documents by former contractor Edward Snowden.

In 2013, leaks showing the NSA had tapped the mobile phone of German Chancellor Angela Merkel caused a backlash in her country, which still bore scars from massive surveillance on the general public carried out by the Nazi and former Communist East German governments.

Sarkozy, according to sources quoted by Le Monde newspaper, denounced what he called "unacceptable methods in general and in particular when it comes to allies."

But France, whose National Assembly votes to pass a law granting the government sweeping surveillance powers to combat terrorism, has traditionally taken a more laconic attitude to allegations of spying than Germany, and the lasting impact on Franco-US relations is likely to be muted. Many French senior officials are saying off the record that while they are unhappy with spying, it is common knowledge that allies do listen in on one another's conversations.

Some French politicians noted the relatively unsurprising nature of the revelations.

"As with every pseudo-revelation about the NSA, it's the spies in Moscow and China who are laughing in the face of Western naivete," tweeted Arnaud Danjean, a center-right member of European parliament and former French security official.

However, with a French presidential election just two years away, the leaks are likely to become a topic of discussion in the campaign, notably on the inadequacy of French counter-surveillance measures and France's love-hate relationship with the United States — a frequent punching bag for both the left and far-right.

"Once again we rediscover that the United States has no allies, only targets or vassals," tweeted socialist MP Jean-Jacques Urvoas.

Indeed European opponents to the TTIP free trade deal between the European Union and the United States are likely to use fresh outrage over U.S. spying to further douse hopes that an agreement will ever be struck. That prospect is already looking remote after the European Parliament decided in June to postpone a vote to endorse the EU's negotiating position.

"France must react firmly and send a strong signal today by withdrawing from the ongoing negotiations on the disastrous TTIP accord," National Front chief Marine Le Pen said in a statement.

She added: "The French must start to realize that the United States, meaning its governments, which we clearly distinguish form its people, are not an allied or even a friendly nation."

The ruling socialist party also struck a harsh tone against the United States.

"How can the United States, which is tied by defense agreements in NATO, decide to listen in to the heads of allied states?" it asked in a statement. "It's not because we knew or suspected this that these massive, systematic and uncontrolled recordings are tolerable."

The leaks suggest that the NSA took a particular interest in listening in to conversations about the Greek debt crisis, which was already preoccupying French and German leaders in 2012, the year that Hollande entered office.

In one intelligence memo titled "Global Sigint Highlights," referring to 'signals intelligence', or phone-tapping, the NSA allegedly referred to a conversation between Hollande and his then-prime minister Jean-Marc Ayrault concerning secret meetings in Paris with German Social Democratic Party officials regarding a potential Greek exit from the euro zone. It also cited to "earlier reporting" about Hollande, in which he complained about Merkel's position on the Greek crisis — suggesting that phone-tapping of the current French president was a frequent occurrence.

According to Mediapart, initials at the top of the document suggest the surveillance was carried out by a "Foreign Satellite." While the leaks do not say which country may have assisted the U.S., previous leaks have shown that German security services at times allowed their satellites to be used for surveillance. Such revelations caused outrage in Germany and prompted the opening of a parliamentary investigation to determine what time of documents Wikileaks had obtained.

Another, earlier document shows a list of tapped lines that includes the mobile phone of Sarkozy ("FR PRES CELL"), his chief of staff, various advisers, the secretary of state for trade, the finance ministry — and even a number in the aviation authority responsible for managing France's government fleet of airplanes.

Correction: This article was updated with the correct name of a French deputy; he is Pierre Lellouche, not Claude Lellouche.