The leaders of Scotland’s political parties are heading to the polls to cast their own votes, along with the rest of the country in a set of elections which could shake up British politics and have profound implications for the future of the United Kingdom.

In Scotland, Scottish Labour's Anas Sarwar voted at his local polling station at Pollokshields Burgh Hall in Glasgow early Thursday morning.

HeraldScotland: Scottish Labour leader Anas Sarwar arriving to vote at Pollokshields Burgh Hall. Image credit: Colin MearnsScottish Labour leader Anas Sarwar arriving to vote at Pollokshields Burgh Hall. Image credit: Colin Mearns

Mr Sarwar is standing against First Minister Nicola Sturgeon in the Glasgow Southside constituency, which includes Pollokshields.

Meanwhile, leader of the Alba party Alex Salmond cast his vote in the Scottish Parliamentary election at Ritchie Hall in Strichen, Aberdeenshire.

HeraldScotland: ALBA party leader Alex Salmond arrives to cast his vote in the Scottish Parliamentary election at Ritchie Hall in Strichen, AberdeenshireALBA party leader Alex Salmond arrives to cast his vote in the Scottish Parliamentary election at Ritchie Hall in Strichen, Aberdeenshire

Scottish Liberal Democrat leader Willie Rennie has already voted by post, as well as SNP's Nicola Sturgeon - although she will join fellow party candidate Rosa Salih at Annette Street Primary School polling station in Govanhill, Glasgow, to lend her support and meet a Syrian family as they cast their ballots.

HeraldScotland: First Minister and leader of the SNP Nicola Sturgeon and candidate Roza Salih outside the polling station at the Annette Street school in Govanhill, GlasgowFirst Minister and leader of the SNP Nicola Sturgeon and candidate Roza Salih outside the polling station at the Annette Street school in Govanhill, Glasgow

Scottish Greens co-leader Lorna Slater will vote at a primary school in Edinburgh, while her fellow co-leader Patrick Harvie will vote at a school in Glasgow.

Scottish Conservative leader Douglas Ross is to vote in Moray.

HeraldScotland: Scottish Greens co-leader Patrick Harvie arrives at Notre Dame primary school, Glasgow. Image credit: Colin MearnsScottish Greens co-leader Patrick Harvie arrives at Notre Dame primary school, Glasgow. Image credit: Colin Mearns

Elsewhere in the UK, and Prime Minister Boris Johnson has cast his London mayoral vote at Methodist Central Hall in London - pictured arm-in-arm with fiancee Carrie Symonds.

HeraldScotland: Boris Johnson and Carrie SymondsBoris Johnson and Carrie Symonds

Boris Johnson sought to manage expectations ahead of the elections, playing down his chances of taking Hartlepool – despite one recent poll putting the Tories 17 points clear and bookmakers making Conservative candidate Jill Mortimer clear favourite to win the seat.

The Prime Minister insisted it would be a “very tough fight” to win Hartlepool, a seat that has been Labour since its creation in 1974.

However, the Conservatives hope to achieve a “hat trick” of successes, winning Hartlepool and retaining the mayoralties in Teesside and the West Midlands.

And in Wales, Welsh First Minister Mark Drakeford and his wife, Clare Drakeford, were pictured arriving to cast their votes in the Welsh Parliamentary Elections.

HeraldScotland: Mark and Clare DrakefordMark and Clare Drakeford

Mr Drakeford hopes to maintain Labour’s grip on the Senedd – but he may find himself forced to forge a new coalition to stay as First Minister.

That could mean talks with Plaid Cymru, whose leader, Adam Price, has committed to an independence referendum within five years if his party wins a majority.

Mr Drakeford is unlikely to concede a referendum as the price for a coalition deal but he has argued for “an entrenched form of devolution” which cannot be rolled back by the UK Government.