The Greens have flagged concerns about the Federal Government's proposed changes to cyber security laws, saying they could be used by foreign governments to "crack down" on political dissidents in Australia.

The Cybercrime Legislation Amendment Bill would allow Australian police and intelligence agencies to give foreign countries investigating cyber crime access to phone and email records.

The new laws would let government agencies compel phone companies and internet carriers to preserve data needed for investigations.

The Government says the authorities need the new powers to operate effectively in the online world.

But Greens Senator Scott Ludlam says while there is a need for agencies to work together on issues such as child pornography, he fears the information could be used by foreign governments to crack down on political opposition.

"We're very concerned for example that governments, more oppressive governments than we might like might use this instrument as a way of cracking down on political dissidents or political activity here in Australia for things that aren't even crimes in Australia," he said.

The Australian Privacy Foundation (APF) says the proposed laws will give excessive powers to intelligence agencies.

But the Privacy Foundation has identified 16 parts of the bill which it says should not be made law, including a lack of protection for human rights.

APF board member Nigel Waters has told a parliamentary inquiry the bill is unacceptable.

"[It contains] grossly unbalanced and excessive legislation powers," he said.

"The Privacy Foundation submits that the committee must find that in its present form the bill is completely unacceptable, incapable of sensible amendment into an acceptable form and should be sent back to the department for further work.

"I think greater collaboration between law enforcement agencies for some of these offences is essential. And there are things that the Australian Federal Police can't do by themselves if this material were posted overseas. So we can see the point."

ASIO has rejected the claim that the proposed cyber crime laws would give it excessive powers and result in privacy abuses.

David Fricker from ASIO says if the laws are not passed it will harm the organisation's intelligence gathering.

"We will miss valuable intelligence around those areas of espionage and terrorism unless we have some mechanism of keeping pace with technology," he said.

"But not only are [they] adequate safeguards - in my opinion adequate safeguards - [that have] been built into these arrangements, it is in fact essential for Australia's security to advance with these kinds of reforms."