"The fate and state of the Doha Round is deeply disappointing," said Zoellick on the opening day of the WTO's review conference on the aid for trade process.
"If leading negotiators think small, they will act small and they miss big opportunities. Dumbing down Doha is defeatist," he said.
"A mini-deal won't do much for growth and it will leave the WTO behind the big changes that we're touching on today," added Zoellick.
Launched at the Qatari capital in 2001, the Doha Round of negotiations for a global free trade deal has stalled amid disagreements between developed and developing countries over proposed tariff cuts on industrial goods and subsidy reductions in the farm sector.
Member states are therefore now considering a mini-deal on areas specific to the poorest states by December.
But Zoellick believes that negotiators should aim for the wider goal.
"I urge the WTO... to think big again. Otherwise, the trade agenda will switch elsewhere," he warned.
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