Voting for the Scottish Conservatives is the "best bet" for supporters of the union to vote tactically to oust SNP MPs, the party's leader has said.

Ruth Davidson made the comments at the launch of her party's local election manifesto on Wednesday after the Prime Minister announced plans for a snap general election yesterday.

The Conservatives won only one Scottish seat at the last general election in 2015 but Davidson has said the party is "optimistic" about increasing the tally when voters go to the polls on June 8.

Davidson said: "I think that it is certainly the case that we are the strongest party to take on the SNP and I know that there was a lot of talk at the general election a couple of years ago about tactical voting, and I've never been a particular proponent of it.

"But I think if you do believe in tactical voting and if your principal belief is in keeping the United Kingdom together and respecting the decision that we made in 2014, actually your vote is for the Scottish Conservatives.

"If you're not supporting the SNP and you want someone to stop their drive to break up Scotland, then the Scottish Conservatives are your best bet."

SNP leader Nicola Sturgeon said if the Conservatives fail to win the election in Scotland then the Prime Minister's opposition to a second independence referendum "will crumble to dust".

Scottish voters will go to the polls before the general election on May 4 to elect local councils.

The Conservatives are proposing to create directly elected provosts for "cities, councils or regions" to mirror metropolitan mayors in England.

The party also want local government to retain revenues from land and buildings transaction tax.

In response to Davidson, Scottish Labour deputy leader Alex Rowley said: "These elections in just over a fortnight are crucial. For the future of our public services, we need to keep the Tories out of our town halls.

"Ruth Davidson's mask has slipped. Her party will plan further spending cuts and privatisation if they get into councils around Scotland.

"We cannot entrust vital services like schools, care for the elderly and housing to a party that delivered the bedroom tax, the rape clause and Jobcentre closures."

A spokesman for the SNP said: "While the SNP campaigns on a positive vision of improving schools, building affordable homes and transforming childcare, the Tories have nothing to offer other than a preoccupation with independence - and this latest call for tactical voting to try and keep the SNP out is a sign of desperation and shows just how obsessed with this single issue they are."