A sign points out the National Security Agency campus in Fort Meade, Md.

WASHINGTON - A presidential advisory panel has recommended sweeping changes to government surveillance programs, including limiting the bulk collection of Americans' phone records by stripping the National Security Agency of its ability to store that data in its own facilities. Court orders would be required before the information could be searched.

In a 300-page report released Wednesday, the five-member panel also proposed greater scrutiny of decisions to spy on friendly foreign leaders, a practice that has outraged U.S. allies around the world.

While the panel's 46 recommendations broadly call for more oversight of the government's vast spying network, few programs would be ended. There's also no guarantee that the most stringent recommendations will be adopted by President Barack Obama, who authorized the panel but is not obligated to implement its findings.

The task force said it sought to balance the nation's security with the public's privacy rights and insisted the country would not be put at risk if more oversight was put in place. In fact, the report concludes that telephone information collected in bulk by the NSA and used in terror investigations "was not essential to preventing attacks."

"We're not saying the struggle against terrorism is over or that we can dismantle the mechanisms that we have put in place to safeguard the country," said Richard Clarke, a task force member and former government counterterrorism official. "What we are saying is those mechanisms can be more transparent."

The review group was set up as part of the White House response to leaks from former NSA contractor Edward Snowden about the scope of the government surveillance programs. Snowden is now a fugitive from U.S. authorities and was granted temporary asylum by Russia. The White House is conducting its own intelligence review, and Obama is expected to announce his decisions in January.

The White House had planned to release the panel's report next month, but officials said they decided to make it public now to avoid inaccurate reporting about its content. It coincided with increased political pressure on Obama following a blistering ruling Monday from a federal judge who declared the NSA's vast phone data collection likely was unconstitutional.

The judge, Richard Leon, called the NSA's operation "Orwellian" in scale and said there was little evidence that its gargantuan inventory of phone records from American users had prevented a terrorist attack. However, he stopped his ruling from taking effect, pending a likely government appeal.

The panel's most sweeping proposal would terminate the NSA's ability to store the telephone data and instead require it to be held by the phone companies or a third party. Access to the data would then be permitted only through an order from the Foreign Intelligence Surveillance Court.

"With regard to the bulk metadata of phone calls, we think there should be judicial review before that information is accessed, and we don't think the government should retain it," Clarke said.

If both recommendations were enacted, it's likely they would slow down the intelligence collection process. The panel's recommendations do allow for exceptions "in emergencies," leaving open the possibility of intelligence agencies scanning the information quickly and asking for permission later if they suspect imminent attack.

The task force did not say how long the phone companies would be required to hold the private data. The phone companies' retention policies vary markedly, according to information recently provided to the Senate Commerce Committee, ranging from one year at Verizon and US Cellular to five years at AT&T and seven to 10 years at T-Mobile.

Representatives of AT&T and Verizon declined to comment on the report and its recommendations. T-Mobile said it would look closely at the proposals. Spokesmen for US Cellular didn't immediately respond to a request for comment.

Another major shift recommended by the task force would tighten federal law enforcement's use of so-called national security letters, which give the government sweeping authority to demand financial and phone records without prior court approval in national security cases. The task force recommended that authorities should be required to obtain a prior "judicial finding" showing "reasonable grounds" that the information sought was relevant to terrorism or other intelligence activities.

The panel also tackled the diplomatic furor over NSA spying on the leaders of allied nations, including Germany. The group recommended that such spying be approved by the highest levels of government and that the decisions be based in part on whether the United States shares "fundamental values and interests" with the leaders of those nations.

The U.N. General Assembly on Wednesday unanimously adopted a resolution aimed at protecting the right to privacy against unlawful surveillance. Germany and Brazil introduced the resolution, which is legally nonbinding, following a series of reports of U.S. eavesdropping abroad, including on Brazilian President Dilma Rousseff and German Chancellor Angela Merkel.

The report was issued a day after a group of top executives from leading technology companies met with Obama at the White House to discuss NSA surveillance and other issues. Several of the companies, including Facebook, Yahoo, Apple, Twitter and Microsoft, have joined to urge Obama to curb the surveillance programs.

In a joint statement Wednesday, the companies praised the "thoughtful and transparent" approach taken by the White House panel in the report. "We look forward to a continued dialogue with the White House as we advocate for meaningful reform of government surveillance practices," they said.

In a nod to critics' complaints that government lawyers had no opposition in secret hearings about NSA programs before the Foreign Intelligence Surveillance Court, the presidential advisory panel urged the creation of a "public interest advocate" to represent civil liberties and privacy interests before the court. The task force did not detail how the advocate would work, but Obama administration officials already have signaled their interest in the idea.

Snowden's disclosures have angered an unusual coalition of liberal Democrats and conservative Republicans on Capitol Hill.

Following the release of the report, Sen. Patrick Leahy, D-Vt., said: "The message to the NSA is now coming from every branch of government and from every corner of our nation: You have gone too far."

Rep. Adam Schiff, D-Calif., who has proposed legislation to shift control of telephone records from the NSA to the phone companies, said the new report was "impressive" and likely will carry a lot of weight for policymakers and Congress. The recommendation regarding custody of phone records by the companies "should put to rest that there's a technological problem" with allowing the companies to hold them, he said in an interview.

Jameel Jaffer, deputy legal director of the ACLU, which has challenged the NSA's surveillance programs in federal court, said Monday's court ruling against the government and now the task force's proposals would "put wind in the sails" of efforts in Congress to scale back the secret operations.

While the White House said Obama was reviewing the full report, he already had decided to pass over one of the panel's recommendations. Last week, officials said the president would continue to allow the NSA director to also oversee the military's cyberwarfare command, ensuring that a military official run the spy agency. The panel recommended that oversight for the units be split, allowing a civilian to head the NSA.