UK votes in most unpredictable election in decades

People walk under a conservative advertising hoarding, featuring David Cameron and Labour party leader, Ed Miliband, on a major road junction near to central London, Britain, May 6, 2015. [Photo/Agencies]

LONDON - British voters get to decide on Thursday who they want to rule the world's fifth-largest economy in a tight election that could yield weak government, propel the United Kingdom towards a vote on EU membership and stoke Scottish desire for secession.

Prime Minister David Cameron's Conservatives and Ed Miliband's opposition Labour Party have been neck and neck in opinion polls for months, indicating neither will win enough seats for an outright majority in the 650-seat parliament.

"This race is going to be the closest we have ever seen," Miliband told supporters in Pendle, in northern England, on the eve of the vote. "It is going to go down to the wire."

Cameron said only his Conservatives could deliver strong, stable government: "All other options will end in chaos."

The Conservatives portray themselves as the party of jobs and economic recovery, promising to reduce income tax for 30 million people while forcing through further spending cuts to eliminate a budget deficit still running at 5 percent of gross domestic product.

Labour says it would cut the deficit each year, raise income tax for the highest 1 percent of earners and defend the interests of hard-pressed working families and the treasured but financially stretched national health service.

If neither wins an overall majority, talks will begin on Friday with smaller parties in a race to strike deals.

That could lead to a formal coalition, like the one Cameron has led for the past five years with the centrist Liberal Democrats. Or it could produce a fragile minority government making trade-offs to guarantee support on key votes.

British stock and bond prices were moderately higher on the final trading day before polling, with election jitters still failing to register any significant investor selling.

The pound was slightly weaker but remained within the relatively tight trading ranges seen over the past three months.

"What is important to us is clarity as soon as possible," Andrew Witty, chief executive of GlaxoSmithKline, Britain's sixth largest company by market value, told reporters.