Scotland's desire for independence is "unstoppable" and must not be blocked by the next Prime Minister, the SNP's Ian Blackford has said.

The party's Westminster leader argued that to refuse Scotland the power to hold another independence referendum would be undemocratic if the SNP wins the most seats in the looming General Election.

Speaking on the BBC's Andrew Marr Show, Blackford claimed that a "move towards independence is unstoppable, it will not change whether there is a Corbyn or a Johnson government in London."

He also said that the SNP were "wanting to lock the Tories out of office" to prevent the UK leaving the European Union, in addition to fighting for a second independence referendum.

"Our priorities, principally, in this election is about making sure we can escape Brexit - that's the first thing - but also securing Scotland's right to choose its own future",

On the issue of securing powers to hold another Scottish independence referendum, he said: "It doesn't matter if it's Jeremy Corbyn or if its anyone else, whoever is Prime Minister has got to respect democracy and the simple fact of the matter is the SNP won the election to the Scottish Parliament in 2016 on a manifesto commitment of a referendum if there was a change of circumstances."

Warning the Tories and Labour to not block another independence vote, he added that if the SNP wins a majority of Scottish seats on a commitment to hold another vote, "it will ill-behold any prime minister to stand in the face of democracy and the right of Scots to choose."

Blackford also sought to blame Tory austerity for one in four people - approximately one million people - living in poverty in Scotland, calling for a commission to look at how to tackle the issue of inequality across the UK.

However, Labour leader Jeremy Corbyn has ruled out holding another independence referendum before the Holyrood elections in 2021, if he becomes Prime Minister following the general election.

Corbyn said he would "certainly not" consider having a ballot on Scotland leaving the UK within his first year of Government.

And the Scottish Conservatives continue to oppose the notion of IndyRef 2 at any stage.

On Saturday their leader Jackson Carlaw said: "The rocks will melt in the sun before a Conservative Government give Nicola Sturgeon her divisive IndyRef 2."

Meanwhile the Lib Dems, who are also against the idea of another independence referendum, have criticised the Scottish Government amid claims of of "secrecy" over how many staff will be taken on to help police officers deal with people in mental distress.

Willie Rennie said Police Scotland had been promised 800 new staff as part of the Government's 2017 mental health strategy.

But he claimed that two-and-a-half years later, the force had only received 7.5 additional mental health workers.

Rennie said: "The fact we have had to ask the Information Commissioner to provide basic scrutiny of this policy shows it is another skin-deep commitment from the Scottish Government.

"There is no good reason for secrecy. If ministers had a robust plan for giving the police more mental health support, they would tell us.

"Instead, we now know that two-and-a-half years after they were promised help, the police have just 7.5 extra staff."

A Scottish Government spokesman said: "As part of Scotland's Mental Health Strategy, we are providing extra investment over five years, rising to £35m in the fifth year, for 800 extra mental health workers in key locations, including police custody and accident-and-emergency departments.

"We are on course to deliver on this commitment, with 327.5 workers having been recruited as of October 1 2019."