A coalition government made up of Labour and the Scottish National Party could break up the UK , Sir John Major warned last night . With the result of May ’ s general election looking very close , the former Conservative prime minister said that a Labour-SNP coalition would be a ‘ lethal cocktail ’ and ‘ a tragedy in the making ’ . Polls suggest that , with no party likely to win enough seats to govern alone , a Labour-SNP coalition is a likely outcome from the election . A coalition government made up of Labour and the Scottish National Party could break up the UK , Sir John Major ( pictured ) warned last night . Sir John , who was Prime Minister between 1990 to 1997 , last night urged Ed Miliband to ‘ summon the courage ’ to formally rule out any deal . The Labour leader , who has so far failed to do so , is due to address Scottish Labour ’ s spring conference this weekend . Sir John said : ‘ The SNP would enter into any agreement with Labour with one overriding aim : To break up the United Kingdom . It is shameful that Labour have not already ruled out even the suggestion . ‘ They would be relying on support from a party that will use every strategy it can to break free from the UK . ‘ Labour now have to make a choice , ’ he wrote in today ’ s Daily Telegraph . ‘ They must summon the courage of their convictions and declare their intent . ‘ The British people – north and south of the border – do not deserve to be misled . ‘ If the outcome of the General Election is inconclusive , will they refuse to govern with the support of a party whose principal aim is to break up the United Kingdom ? ’ Sir John , who was Prime Minister between 1990 to 1997 , last night urged Ed Miliband ( pictured ) to ‘ summon the courage ’ to formally rule out any deal . As prime minister , Sir John warned that devolution could lead to Scotland ’ s independence . He said he was now speaking out as ‘ an Englishman with a profound admiration and respect for Scotland ’ . ‘ At Westminster , SNP minds would not be focused on the well-being of the United Kingdom , but on their own party interests , ’ he added . ‘ In collaboration , the two parties would make common cause at the expense of their natural enemies . For Labour , that will be to pick the pockets of the Tory shires ; and for the SNP , to boost Scotland at the expense of the rest of the UK. ’ Ed Miliband is facing increasing demands from senior Labour figures to rule out a power-sharing deal with the SNP . Senior MPs are demanding the Labour leader uses a keynote speech at the Scottish Labour conference in Edinburgh tomorrow to make his position clear . Mr Miliband is said to be ‘ waiting for the right moment ’ to rule out a deal . But there is concern that he may only be prepared to rule out a formal coalition – leaving open the possibility of the SNP propping up a Labour-led government in key votes in exchange for concessions to Scotland . David Cameron has branded an electoral pact between Labour and SNP ‘ the ultimate nightmare ’ .
John Major warns coalition between Labour and SNP could break up UK . Former Prime Minister says the pact would be a 'tragedy in the making ' Polls suggest Labour-SNP coalition is a likely outcome from the election . Score: 6