Liberal Democrat leader Sir Ed Davey has told how Alex Salmond’s proposed return to the Scottish Parliament “should send shivers down the spine”, as he warned the new Alba Party leader could become Russian President Vladimir Putin’s “spokesperson in Holyrood”.

His comments came after former Scottish first minister Mr Salmond refused to say whether he believes Russia was behind the Salisbury poisonings in 2018 – in which Sergei Skripal, a former Russian military officer, and his daughter Yulia were attacked.

Speaking on the third anniversary of the attack last month, UK Defence Secretary Ben Wallace said Russia remains an “adversary” of the UK.

Mr Skripal, a former Russian spy turned double agent for MI6, and his 33-year-old daughter were left seriously ill after coming into contact with the deadly nerve agent Novichok.

Asked repeatedly if Russia was responsible for the incident, Mr Salmond told BBC Radio Scotland on Wednesday morning: “Evidence came forward, it was contested, I said it should go to the international tribunals and courts, I said that at the time.”

The former first minister, who has a show on the Russian state-controlled RT channel, insisted there has been no interference with his programme – which he produces along with Tasmina Ahmed-Sheikh, a former SNP MP who is now an Alba Party candidate.

Mr Salmond insisted: “Not a single word of editorial instruction or even suggestion has been made to me by anybody in RT, and the programme stands on its own merits.”

Sir Ed, campaigning in Scotland on Wednesday ahead of May’s Holyrood election, said he was “deeply shocked” by the former first minister’s comments.

“Just because he has been doing Russia Today and Moscow has been bank-rolling him in the last few years, doesn’t give him the right to say things like that which are clearly not true, fly in the face of all the evidence,” Sir Ed said.

“The idea that you have Mr Putin’s spokesperson in Holyrood should send shivers down the spines of people, it is quite shocking.”

Scottish Liberal Democrat leader Willie Rennie also told how he had been “horrified” by Mr Salmond’s comments.

Mr Rennie said: “To minimise the role of Russia in the Salisbury poisonings, or to question the role, just shows how far he has plummeted – from somebody who was the leader of our country, respected, even if you disagreed with him, to some apologist to Putin.

“It will be a horrifying prospect if he is in the Scottish Parliament after May.”

He added that it shows “just why we can’t afford to take a risk with the nationalists any more”.

Scottish Conservative candidate Annie Wells joined in the criticism, saying: “This car-crash interview only served to highlight again that Alex Salmond is not fit to hold public office.

“His appalling refusal to condemn Russia for the Salisbury poisonings shows how deep in the pocket he is to his Kremlin paymasters.

“Alex Salmond may not have seen the relevance of being questioned about his links with Russia but voters will be astonished at his continued lack of moral judgment.”