WTO negotiators reached a breakthrough on the most contentious issue of the six-day trade talks, agreeing that wealthy countries would eliminate farm export subsidies by 2013, paving the way for a modest agreement to cut trade barriers across various sectors, according to a copy of the final draft agreement obtained by journalists. The breakthrough, coming after all-night negotiations, appeared to save the World Trade Organization meeting from an embarrassing collapse _ provided the final draft is approved by all 149 member nations and territories meeting later Sunday. But the draft represents a far less ambitious agreement than WTO negotiators had originally hoped to achieve in Hong Kong: a detailed set of formulas for cutting farm and industrial tariffs and subsidies. The revised text sets April 30, 2006, as a new deadline to work out those details, a key step toward forging a global free trade treaty by the end of next year, the Associated Press reported.