Speaking in Fife, Sir Ed said an appearance on RT’s Alex Salmond Show by his predecessor, Vince Cable, during the Ukraine crisis was “an error of judgement”.
But Sir Ed stressed the former Lib Dems leader had been “extremely critical of Putin” and the situation was "very different” from former first minister Salmond, who had been a long-term host on the Kremlin-backed programme.
Sir Ed said he agreed with Scottish Liberal Democrat leader Alex Cole-Hamilton, who had called for Mr Salmond’s Privy Council membership to be revoked.
He said: “The Liberal Democrats are strong supporters of Nato and strong critics of Putin. We are calling for the strongest possible sanctions, far strong than what [Boris] Johnson is calling for, and that’s in complete contrast with Salmond.”
The oligarch tax was proposed by Sir Ed as a potential solution to help “the most vulnerable” and those struggling with energy bills.
Sir Ed said: "When we go after, as we should be now, freezing and being in the process of seizing the assets of Putin’s cronies, who have such large money-holding, share-holding properties in the UK, we should be using that money alongside the windfall tax that I have been pushing for so long to make sure we can support the most vulnerable and those struggle with their energy bills.
“So many families here in Fife and across the UK are facing real misery with the cost of living and Putin’s cronies have been getting away with it and that’s why Johnson’s government is so wrong to be so weak in sanctioning his cronies.
"The oligarch tax alongside the windfall tax are all measures to fund a huge amount of support that we are arguing to help people with their heat bills.”
Sir Ed said Scotland’s transition away from North Sea oil would “take some time” and it would need to be done “in a controlled and planned way”.
Talking about the need to reduce the amount of gas and oil used by the UK, Sir Ed said: "We need to invest in green energy in the future, which Scotland is so rich in.”