WASHINGTON - An outside panel appointed by US President Barack Obama has outlined 46 recommendations to limit the National Security Agency's secret surveillance programs, but above all found the programs should stay in place, according to the review report released by the White House Wednesday.

The report was released by the White House following a meeting between Obama and the five members of the advisory panel on Wednesday morning, ahead of its original schedule of release.

"Because our adversaries operate through the use of complex communications technologies, the National Security Agency, with its impressive capabilities and talented officers, is dispensable to keeping our country and our allies safe and secure," wrote the executive summary of the 308-page report.

The panel has recommended "a series of significant reforms" with respect to surveillance of US persons, including tighter limits of the NSA's controversial domestic telephone surveillance programs.

The panel recommends that the Congress should end the current bulk storage of telephone metadata, which "creates potential risks to public trust, personal privacy, and civil liberty." Instead, such metadata should be held either by private providers or by a private third party, in case the government might need such an access, said the panel in its report.

The report also recommends limits on spying on non-US citizens and particularly foreign leaders, following diplomatic uproar aroused by the disclosures of US snooping of the public and the leaders of other countries, including its European allies.

The panel recommends the government should consider five criteria before it makes the decision to conduct surveillance of foreign leaders, including whether there is a need to conduct such surveillance to assess "significant threats" to US national security, as well as what would be the negative effects if the foreign leader or foreign citizens became aware of the surveillance.

The report also said the US government should explore "understandings and arrangements" on intelligence collection guidelines and practices "with a small number of closely allied governments".

However, it is not clear whether those sweeping but modest recommendations will be enacted. The controversial surveillance programs have made headlines and triggered outrage home and abroad since they were first disclosed in June with the leaks by former defense contractor Edward Snowden.

The Obama administration has vowed to make some changes to the controversial surveillance programs, in an effort to rebuild public trust. But the president, supporters in Capitol Hill, and intelligence leaders have also defended the NSA's work in the past months.