The Irish government’s chances of winning next week’s referendum on the European Union’s Lisbon reform treaty were boosted on Tuesday when the influential Irish Farmers’ Association voted to recommend a Yes vote.

The 80,000-strong IFA backed the treaty after Brian Cowen, the prime minister, promised the farmers that he would use Ireland’s veto in the European Council to block agreement on liberalisation plans in the ­current round of World Trade Organisation talks in Geneva.