LONDON - Polls have closed in Britain, where voters cast their ballots Thursday in a tightly contested general election that appeared unlikely to yield a workable parliamentary majority for either of the main parties.
Some opinion polls put Prime Minister David Cameron's Conservative Party marginally ahead of its main rival, Labour, with both parties around 34 per cent.
In two of the final polls, Ipsos MORI for London's Evening Standard gave the Conservatives 36 per cent and Labour 35 per cent, while ICM for the Guardian put Labour on 35 per cent and the Conservatives on 34 per cent.
The Conservative-supporting Daily Mail tabloid called it "the most unpredictable election in a generation," reporting that 25 per cent of voters were still undecided on polling day.
Sunny weather in many areas was expected to boost turnout to more than 70 per cent of eligible voters, or some 30 million people, with a higher figure of about 75 per cent forecast in Scotland.
Exit polls were scheduled to be released after polling stations closed at 10 pm local time, 4am in Thailand.
The outcome of the election will determine Britain's economic direction and could have major implications for the country's welfare services, its relationship with the European Union - and even the future integrity of the nation.
In a Twitter message, Cameron urged people to "vote for a stable government and a strong economy," asking for five more years in power.
Labour Party rival Ed Miliband urged voters to choose "a government that puts working people first" and reject the Conservatives' plan that "always puts the rich and powerful first."
Miliband, Cameron and Deputy Prime Minister Nick Clegg, leader of the Liberal Democrats, were among the early voters.
Caroline Lucas, Britain's only Green Party member of parliament, voted with her 19-year-old son in her Brighton Pavilion constituency.
The Greens leader since 2012 is Natalie Bennett, an Australian-born journalist who worked at the Bangkok Post in the mid-1990s immediately before she emigrated to England.
Under Britain's first-past-the-post, constituency-based system, the two major parties are expected to win about 550, or 85 per cent, of the 650 parliamentary seats between them.
Neither party is expected to win a parliamentary majority, leading to a repeat of the 2010 election, which produced a hung parliament.
Cameron and Miliband are both expected to try to form a minority government or a coalition with one or more smaller parties.
The anti-EU UK Independence Party (UKIP) is forecast to attract the third-highest number of votes, between 11 per cent and 16 per cent, but should win only a handful of seats.
The Liberal Democrats - the Conservatives' coalition partners in the outgoing government - are forecast to win about 9 per cent of the vote, with the Greens on 5 per cent and the Scottish National Party taking most of the 59 seats in Scotland.
The SNP could gain enough seats to give a Labour-SNP informal alliance a majority in parliament as many former Labour and Liberal Democrat voters have said they are switching their support.
"People have tried to hijack this election and say it's another [Scottish] independence referendum," teacher Jackie Coburn, 52, told dpa outside a polling station in Edinburgh.
"I think Labour are going to be punished in Scotland today," said Coburn, who voted SNP for the first time.
"I'm a Green voter really, because of the environment, but I'm going with the SNP," said builder Allan Rooney, 31.
"I know that the SNP are going to push for what I want for Scotland, but they're not going to put Scotland above the other people in the UK. There's a huge gap between the rich and the poor, the higher and the lower, and it's got worse under the Tories (Conservatives)."
In many areas outside London, voters Thursday elected nearly 10,000 members of 290 local councils.