WASHINGTON: President Barack Obama sought Monday to allay fears about secret US intelligence programs, rejecting comparisons with the policies of his predecessors George W. Bush and Dick Cheney.

The Obama administration has been on the defensive since last week's dramatic leak of details of two huge operations by the National Security Agency to track US citizens' phone calls and intercept global Internet traffic.

One poll had the president's approval rating falling by eight points, and some of his progressive allies have joined attacks against him by his usual conservative and libertarian opponents.

Responding on the “Charlie Rose” show on PBS television to the charge that he had merely continued with the surveillance policies that ex-president George W. Bush and former vice president Dick Cheney had brought in after the 9/11 attacks, Obama pushed back.

He defended the NSA data-gathering programs, insisting that they were carried out with “systems of checks and balances” adding: “Congress is overseeing it, federal courts are overseeing it.””The whole point of my concern, before I was president -- because some people say, 'Well, you know, Obama was this raving liberal before. Now he's, you know, Dick Cheney,'” Obama said.

“Dick Cheney sometimes says 'Yeah, you know? He took it all lock, stock and barrel.' My concern has always been not that we shouldn't do intelligence gathering to prevent terrorism, but rather are we setting up a system of checks and balances?

”But the president also said he recognized the “legitimate concern” raised by news reports, and that he had ordered intelligence officials to declassify as much as possible “without further compromising the program.”And he promised that an independent advisory board would review the programs.

“I've stood up a privacy and civil liberties oversight board, made up of independent citizens, including some fierce civil libertarians,” he said.

“I'll be meeting with them. And what I want to do is to set up and structure a national conversation, not only about these two programs, but also the general problem of data, big data sets, because this is not going to be restricted to government entities.

”The leaks indicated that the NSA and FBI get vast amounts of data from US Internet companies, to allow for round-the-clock monitoring of emails, documents, video, social media posts and photos online.

Another program gathers mountains of call data from major telecom operators.

Obama said he hoped some transparency would help set the record straight on the programs.

“If you're a US person, then NSA is not listening to your phone calls and it's not targeting your emails unless it's getting an individualized court order. That's the existing rule,” he said.

“We're going to have to find ways where the public has an assurance that there are checks and balances in place, that they have enough information about how we operate that they know that their phone calls aren't being listened into, their text messages aren't being monitored, their emails are not being read by some Big Brother somewhere.”