WASHINGTON – In overhauling the nation’s spy programs, President Obama vowed Friday that he “will end” the bulk telephone data program that has caused so much consternation – “as it currently exists.”

The caveat is important. Although Obama imposed some new conditions on the program, the National Security Agency, for the time being at least, will continue to maintain and tap into its vast catalog of telephone data of tens of millions of Americans until someone can think of another way to do the same thing.

The series of surveillance changes offered by Obama on Friday were intended to reassure a wary public without uprooting programs that he argued have helped protect the country.

In his most extensive response to revelations by Edward J. Snowden, the former NSA contractor, Obama ordered more transparency and instituted more safeguards, but he either passed over the most far-reaching recommendations of his own review panel or left them for Congress and the security agencies themselves to hash out.

“The reforms I’m proposing today should give the American people greater confidence that their rights are being protected, even as our intelligence and law enforcement agencies maintain the tools they need to keep us safe,” Obama said in his speech at the Justice Department. “And I recognize that there are additional issues that require further debate.”

Obama announced carefully calculated changes to surveillance policies, saying he would restrict the ability of intelligence agencies to gain access to telephone data, and would ultimately move that data out of the hands of the government. But Obama left in place significant elements of the broad surveillance net assembled by the NSA and left the implementation of many of his changes up to Congress and the intelligence agencies themselves.

In the much-anticipated speech that ranged from lofty principles to highly technical details, Obama said he would require prior court approval for the viewing of telephone data. He also said he would forbid eavesdropping on the leaders of allied countries, after the disclosure of such activities ignited a diplomatic firestorm with Germany and other friendly nations.

But Obama also delivered a stout defense of the nation’s intelligence establishment, saying that there was no evidence it had abused its power, and that many of its methods were necessary to protect Americans from a host of threats in the years after the Sept. 11, 2001, terrorist attacks.

At the heart of the changes will be an overhaul of the bulk data program that has swept up many millions of records of Americans’ telephone calls, though not their content. Although Obama said such collection was important to foil terrorist plots, he acknowledged it could be abused and had not been subject to an adequate public debate.

The bulk data program seemed to cause the most difficulty for the president as he pondered what to do about it. His review panel suggested taking the data out of the NSA’s hands and leaving it with telecommunications companies or a newly created independent entity. The NSA could then tap it only in certain instances while investigating terrorist links. Obama deemed both ideas unworkable and so put off a decision by saying he supported the goal of removing the data from the NSA but would ask Attorney General Eric H. Holder Jr. and James Clapper Jr., director of national intelligence, to come up with a way of doing that.

In the meantime, he set a new rule that “the database can be queried” only with permission from the Foreign Intelligence Surveillance Court, which oversees secret spying operations. But he allowed an exception “in the case of a true emergency.” He did not define what would constitute such an emergency or who would determine whether a situation qualified. Nor did he clarify whether the surveillance court would have to approve each time a new telephone number was searched or each time a new target was searched. But some program supporters expressed concern that it could take too long.

Obama argued that the programs that have become so disputed had not been abused and yet needed reform to avoid the perception of abuse. And as he tried to satisfy critics by embracing their concerns, Obama also seemed determined to avoid alienating many of the major players involved in the country’s intelligence programs.

He deferred to James B. Comey, the FBI director, by rejecting a proposal by his review panel to require court approval of administrative subpoenas known as national security letters. He avoided offending Chief Justice John G. Roberts Jr. by declining to accept a recommendation to take away his unilateral power to appoint every member of surveillance court.

Civil liberties advocates who had pressed Obama to do more reacted with a mix of optimism and disappointment.

“While I appreciate the president’s effort to strike a better balance between the twin imperatives of protecting Americans from harm and ensuring their civil liberties, the steps he announced today fall short of reining in the NSA,” said Rep. Peter Welch, D-Vt.

“President Obama’s announced solution to the NSA spying controversy is the same unconstitutional program with a new configuration,” said Sen. Rand Paul, R-Ky., an NSA critic.

Supporters of the intelligence programs, on the other hand, were skeptical, worrying that the immediate changes ordered by Obama may produce more procedural hurdles, and that the larger changes still possible down the road would hinder the search for terrorists.

Meanwhile, Obama made no mention of two of the recommendations from the panel that looked into surveillance that are of most pressing concern to Silicon Valley and the business community: that the NSA “not in any way subvert, undermine, weaken or make vulnerable” commercial software, and that it move away from exploiting flaws in software to conduct cyberattacks or surveillance.

The president has been sharply criticized by companies that protest that the NSA’s practices are costing them billions of dollars in foreign sales to customers in Europe and Asia who fear that American products have been deliberately compromised by the agency.