Scrapping Scotland 's Trident nuclear deterrent is a key SNP policy . Ed Miliband has insisted Labour will not compromise over Trident renewal . Nicola Sturgeon has revealed SNP could still prop up the Labour Party . Labour MPs are urging Ed Miliband to rule out a deal with the SNP . Latest polls suggest the SNP could win up to 56 of Britain 's 59 seats .
Scrapping Britain 's Trident nuclear deterrent is a key SNP policy . Ed Miliband has insisted Labour will not compromise over Trident renewal . Nicola Sturgeon has revealed SNP could still prop up the Labour Party . Labour MPs are urging Ed Miliband to rule out a deal with the SNP . Latest polls suggest the SNP could win up to 56 of Scotland 's 59 seats .