Long Yongtu, who negotiated China’s entry into the World Trade Organisation, openly criticised his country's tactics and warned it would never get a trade deal.
He told an annual conference organised by Caixin, an influential Chinese financial media outlet, it was inappropriate to involve political considerations in trade talks.
Mr Long said: “If we have people who always talk about politics engaging in trade negotiations, we will never have a deal.
He said it was unwise to impose import duties on soybeans in retaliation for US President Donald Trump’s decision to slap additional levies on Chinese imports.
Mr Long said: “Agricultural products are very sensitive in trade and soybeans are very sensitive as well.
“We should have avoided targeting agricultural products because targeting agricultural products should be the last resort.