London, Dec 12 (TIWN) UK Prime Minister Boris Johnson on Thursday became the first leader of a major political party in Britain as he cast his ballot in one of the country's most crucial and decisive general election.

In their last interviews with the BBC ahead of Thursday's poll, Mr Johnson repeated his main pledges, saying: "Only if you get Brexit done [can you] move the country forward."  Meanwhile, Mr Corbyn said there was a "greater understanding" from the public that the country "cannot go on with underfunded public services".  The polls will open at 07:00 GMT.  Both leaders held their final rallies in London on Wednesday night.  Leaders in final push for votes ahead of election WATCH: What's the election been about? Other party leaders also travelled the country on the last day before the election to win support from undecided voters.  Liberal Democrat leader Jo Swinson said votes for her party could stop Brexit, adding: "Our country can be better than what Boris Johnson and Jeremy Corbyn are trying to say is the only way forward."  The SNP's Nicola Sturgeon said a vote for her party was a vote to stop further cuts to public services and to "stop Scotland being dragged out of the EU against its will".