Counting has begun in the Irish general election, as exit polls suggest a close contest between the three major parties.

The Republic of Ireland elects its government using a system of proportional representation known as the single transferable vote. Voters rank candidates in their constituency in order of preference, marking their favourite with a number one, a number two beside their next choice and so on.

The exit poll put the left wing Sinn Fein on 21.1%, the centre-right Fine Gael of Prime Minister Simon Harris on 21.0% and like-minded coalition partner Fianna Fail on 19.5%. Fine Gael and Fianna Fail pledged ahead of the election to seek to form a coalition without Sinn Fein,

Irish Prime Minister Simon Harris’s Fine Gael party is locked in a virtual dead heat with Sinn Fein in the general election, suggesting his decision to go to the country early didn’t yield the advantage he predicted.

Ireland's main opposition party Sinn Fein looked on course to narrowly win the most votes at a general election on Friday, but its two main centre-right rivals will likely have enough seats to govern again without it,