Scotland's international reputation has been damaged by Alex Salmond's decision to host a talk show on state-funded Russian television, Willie Rennie has claimed.
The Scottish Liberal Democrat leader said the former first minister's choice of RT as a platform for his latest venture "should turn our stomach".
Mr Rennie called on the Scottish Government to distance itself from Mr Salmond during First Minister's Questions at Holyrood.
But Deputy First Minister John Swinney, standing in for Nicola Sturgeon, accused opposition parties of "hypocrisy".
The exchange followed comments by Tiina Intelmann, the Estonian ambassador to the UK, at the parliament's Europe Committee describing RT as "a Kremlin arm of propaganda".
Mr Rennie questioned whether Mr Salmond, who is seeking to become chairman of the newspaper group Johnston Press, was a "fit and proper person" to own newspapers.
He said: "Newspaper regulation is devolved... so it's reasonable to ask whether Alex Salmond would be a fit and proper person to own the Scotsman when he is being paid by President Putin's propaganda channel.
"We should remember, this is the TV channel that seeks to undermine western democracy and ignore human rights abuses at home.
"It should turn our stomach that a former first minister of this country is giving it credibility and legitimacy by launching this show this very day.
"Scotland's reputation abroad has been damaged. Countries, small countries, particularly along the Russian border, will be deeply concerned by this decision. Alex Salmond does not speak for Scotland on this.
"So what is this government doing to actively distance themselves from Alex Salmond?"
Mr Swinney highlighted that Ms Sturgeon had made clear RT would not have been her channel of choice.
Guests on the first broadcast of The Alex Salmond Show on Thursday included deposed Catalan president Carles Puigdemont, Tory MP Crispin Blunt and Labour peer Baroness Helena Kennedy.
He said: "I understand, although I've not seen it myself, that on the programme that has been broadcast today Mr Salmond had guests from both the Labour party and the Conservative party on his programme. So I suspect that reflects the plurality of choice that will be in his guests."
Pointing out that UK Lib Dem leader Vince Cable had also appeared on RT in 2015, he added: "This is an issue that Alex Salmond, who is not currently an elected politician, is free to take forward as he wishes.
"But I think what is also fair for me to say in all of this is that the whole debate has been struck by a stinking reek of hypocrisy from every other political party."
Mr Salmond recorded an interview with Mr Puigdemont at an undisclosed location in Belgium, where the Catalan leader fled when Spanish authorities decided to press charges against him after the independence referendum in Catalonia.
The Madrid government - which opposed the referendum taking place - dissolved the regional Catalan parliament after it voted in favour of a unilateral declaration of independence, and called snap elections for December.
During the interview, Mr Puidgemont said there was an "an intellectual incapacity" on the part of the Spanish government "to admit the possibility, the real possibility, that Spain could be different in future".
He said: "The message is to be confident, passionate and resilient because we will win. We will succeed. Finally, democracy will prevail."