The 149-nation WTO has acknowledged that it will miss an April 30 deadline for an accord on a key plank of the talks: the mathematics for cutting customs duties and other trade barriers.
Members had fixed the target at a WTO conference in Hong Kong last December, where trade ministers reached a last-minute deal that was meant to steer the Doha Round towards a successful conclusion at the end of this year.
The round was launched in 2001, marking an attempt to slash global trade barriers and use commerce to boost developing countries.
The talks were meant to end in 2004, but they have been on a rollercoaster from the outset.
They broke down in 2003 as rich and poor countries argued over the level of concessions required, then picked up speed in the summer of 2004 after an interim deal, before getting mired again until a flurry of new proposals in the months leading up to the Hong Kong conference.
Economically, a failure to finish the Doha Round could mean missing out on the 290 billion