He claimed Nicola Sturgeon’s lack of credibility over claims that she would secure an independence referendum by next year meant the constitution could not be relied upon to “turbo-charge” an election campaign.
Writing in The Sunday Times, he said the idea of a new party was “inevitably attracting new supporters from across the party membership”, adding: “Yes, there may be risks to a split with the UK party – but are they any greater than the risks inherent than in the status quo?
“One thing is certain – continuing chaos in Downing Street is holding back Scottish Tory prospects and will put at risk good, hard-working Scottish Conservative councillors and MSPs unless something changes.”
At the last council elections, the Tories narrowly returned more councillors than Labour. However, polls suggest a series of controversies surrounding Mr Johnson have dented support ahead of May’s vote.
At the Holyrood elections last year, the party held on to the 31 seats it won in 2016 and the SNP was denied a majority in what was seen as a strong result for Douglas Ross, the current leader.
A spokesman for the Scottish Tories said: “As we enter the New Year, the Scottish Conservatives are the only opposition that is strong enough to stand up to the nationalist coalition. We will be putting up candidates all across Scotland to fight the crucial council elections as we build Scotland’s real alternative to the SNP at every level of government.”