If Westminster fails to create a UK-wide press regulator when it votes on Monday, Holyrood should create one in consultation with the media, the expert group on the Leveson Report in Scotland said in a report released yesterday.
Scottish Tory leader Ruth Davidson said: "This is a shameless attempt by the First Minister to shackle a free press at a time of the utmost political sensitivity.
"The expert group was instructed by Alex Salmond to find ways of implementing a law to control the press and that's exactly what it has done."
The regulator could have the power to censure newspapers, magazines and websites, including "gossip" sites, while further regulation of social media such as Twitter may also be required, the group stated.
Voluntary press regulation is unlikely to work, the panel chaired by former Solicitor-General for Scotland Lord McCluskey said.
The panel's report read: "The carrots proposed by Leveson are not sufficiently enticing, nor the sticks sufficiently intimidating, to put any real pressure on publishers to join a scheme that replaces light touch self-regulation."
Scottish LibDem leader Willie Rennie said: "The proposal to compel newspapers to join a regulated body was unexpected. The potential consequences of that need to be properly looked at."
Scottish Green co-convener Patrick Harvie said: "Greens support the implementation of the Leveson proposals, but the McCluskey report appears to go much further than anyone had expected.
"I cannot see how this is remotely practical, even if it was desirable."
Mr Salmond said he hoped Holyrood could find common ground.
He said: "While there is a uncertainty and division surrounding how Westminster is going to take forward the Leveson recommendations, I am hopeful that in Scotland all parties can continue to work together to find an acceptable way forward."
The Scottish Newspaper Society warned that a Scotland-only solution would be damaging to already struggling newspaper publishers.
A spokesman said: "The Society is in favour of UK-wide, non-statutory regulation and is opposed to a Scotland-only solution, which we believe will be a costly burden on many small publishers who are already facing economic hardship."