Peter Cruddas secretly taped making Tory Union claims
Footage has emerged of former Conservative Party treasurer Peter Cruddas saying the Tories need to be seen as fighting to keep the Union, even if they do not agree with it.
He is seen making the claim in secret Sunday Times recordings.
Mr Cruddas resigned on Monday after footage appeared to show him offering access to the prime minister in exchange for £250,000 donations.
The SNP called it "a bombshell" but the Tories said they supported the Union.
Scotland's Deputy First Minister Nicola Sturgeon said it showed the Tories were "cynically faking" their opposition to independence.
A Scottish Conservative Party spokesman said: "The prime minister has always been very clear that he wants to keep the Union together.
"Indeed the transcript shows that the prime minister privately told Peter Cruddas that his true feelings are to support and to fight for the Union. One of our fundamental beliefs as a Party is that the United Kingdom is better off together."
In the latest release of tapes, which were recorded by reporters posing as potential donors, Mr Cruddas seems to be suggesting arguing for the union would put the party in a stronger negotiating position after the referendum.
He said: "We, as a party, have to be seen to be fighting to keep the Union together.
"Even if we don't agree with it, because at the end of it all, if the Scots say we're out of here and they want to go independent, we can turn around and say it's not what we wanted, it's not what we campaigned for, you can't have this, you can't have that, and you can get on with it."
In the video, Mr Cruddas also appears to describe First Minister Alex Salmond as "the mad Scotsman".
Ms Sturgeon said: "This is another bombshell for the Scottish Tories who are isolated and irrelevant in the games being played by their London bosses.
"It shows that senior Tories in London are cynically faking their opposition to independence to position themselves for a post independence deal.
"The Cruddas revelations show that they believe in nothing except protecting Westminster interests.
"Their claims about winning the referendum are exposed as mere bravado. In fact they are already preparing for losing."