Republican electors due to cast the votes on Monday that will seal Donald Trump's presidency, are facing death threats and organised campaigns in a ditch bid by desperate opponents to avert the outcome of the US election.

Amid concerns that Russia intervened in the election, members of the Electoral College have been bombarded with calls to post-pone this final seal of approval - or choose a different candidate for the presidency.

"This is absolutely unique," Mary Barket, an elector and long time Republican politician in Pennsylvania, a crucial swing state which broke for Mr Trump, told The Telegraph.