British voters have overwhelmingly rejected plans to change the 'first-past-the-post' voting system in a nationwide referendum.

After a divisive campaign that saw the Coalition partners on opposing sides of the argument, the No vote stormed ahead and won 68% of the vote.

The victory deals a huge blow to the junior partner in Britain’s coalition government, the Liberal Democrats. The Liberals had supported the Alternate Vote system, where voters rank candidates in order of preference.

In fact, the referendum was one of the key demands made by the Liberal Democrats when they agreed to form a coalition with the Conservatives.

LibDem leader and deputy prime minister Nick Clegg admitted it was a "bitter blow" to lose the vote, hours after his party suffered heavy losses in council, Scottish Parliament and Welsh Assembly elections.

His fight to change the electoral system was opposed by prime minister David Cameron and the Conservatives in what became an increasingly fraught contest.

Yes campaigners including Clegg accused their opponents of lying about Alternative Vote, particularly over whether it would cost more or require the introduction of voting machines.

The Yes camp denied this claim, but the No campaign stuck to its guns.

Provisional figures from the Electoral Commission suggested turnout was 41.8%, with 19.1m votes cast.