Europe will "lose more than it gains" if it starts a trade war with China, a former senior Belgian diplomat has warned.

"I am quite convinced that China's development is the hope of European integration," said Patrick Nijs, who left his position as ambassador to China earlier this year. "But if we start a trade war, Europe will lose more than it gains."

His warning comes as the European Union and China are in the critical, final stages of negotiations over solar panels.