The SNP’s deputy Westminster leader has said she might vote against her party after independence as she appeared to give lukewarm backing to the Scottish Government.

Mhairi Black, who is standing down from the Commons at the general election, said her vote would be “up for grabs” after a Yes as the SNP would have served its purpose.

Asked if the SNP had been in power too long, the Paisley MP sighed and told an audience on the Edinburgh Fringe: “What’s the other options?”

Ms Black, 28, also said she didn’t know if Scotland would be independent in a decade, but thought it would be “one day” when enough people think “we can do something better, what have we got to lose, we’ll try something different”.

She said: “Whether that happens in the next two years or the next 10 years, I don’t know, but I have no doubt that Scotland will one day be independent, no doubt about it at all.”

Ms Black, who was the youngest MP in the Commons when elected in 2015, was speaking at an In Conversation event at the Stand New Town Theatre with journalist Graham Spiers.

She said she was quitting Westminster because she was surrounded by “a***holes” for much of the week and did not know what she was going to do next with her life.

However she refused to rule out a move to the Scottish Parliament, saying: “I’m not closing myself off to anything but once I stop at Westminster I think my initial plan is just to breathe for a moment and figure out what I want to do and see what opportunities lie in front of me.

“So we’ll see, we’ll see.”

Speaking about independence, she said Labour and the Tories had the most to gain from it as they could break free of London and their past, but the SNP’s job might be done.

She said: “If anything the political party that’s got the most to lose from independence is the SNP because it’s arguably served its purpose.

“You’ve got folk like me openly saying, they want independence, my vote’s up for grabs.”

Asked if the SNP had been in power too long after 16 years, Ms Black hesitated for a few seconds and hummed and sighed before saying: “I’m going to say No, predictably.

“I totally appreciate the sort of sentiment with that [question]. But I think, see ultimately, particularly in Scotland, what’s the other options?

“Because I think that see if the SNP and the Greens come out of the Government at Holyrood, I think folk are going to get a real shock when all of a sudden tuition fees are coming back, your prescriptions not free, you’re getting charged for that spare bedroom that was getting mitigated for all those years without anybody talking about it.

“So I still think that the SNP, and certainly this coalition, is the best thing on offer in Scotland just now.

“And by no means is it perfect, and there’s always room for improvement, but when I really stop and think about what the alternatives are I do still think the SNP is offering the best hope for people just now, particularly those who are struggling the most.

“So, yeah, I’d still vote [for them].”