British Prime Minister David Cameron conceded on Sunday that Scotland had what it takes to be an independent nation, but said it currently enjoyed "the best of both worlds", imploring it not to break the United Kingdom apart. Stepping up his government's campaign to hold Britain together ahead of an independence referendum expected next year, Cameron urged Scotland not to sever a union with England that dates back 306 years. "Put simply: Britain works. Britain works well. Why break it?" he wrote in an article published in Scottish newspapers. "This big question is for Scotland to decide. But the answer matters to all of our United Kingdom. Scotland is better off in Britain. We're all better off together and poorer apart." Cameron's political future and historic legacy are on the line. He has pledged to contest the next British general election in 2015 and his own Conservative party would never forgive him if he presided over the break-up of a United Kingdom comprising England, Scotland, Wales and Northern Ireland. London's main parties are campaigning jointly against independence, knowing that Alex Salmond's Scottish National Party (SNP) is an astute and highly motivated political machine that will spare no effort to win a vote on its flagship policy. Tapping into an emotive cocktail of historical rivalry, opposing political tastes, and a perception that the British parliament in London does not nurture Scotland's national interests, the "Yes Scotland" campaign wants independence to be a reality by 2016.