GCC states are optimistic they will see progress on removing a six per cent duty imposed by the European Union on their primary aluminium exports soon, a government official in Dubai, UAE said.

"By the end of the summer we might be able to have a positive answer provided the (GCC) countries continue to apply the maximum political pressure on the EU," Khalid Buhmaid, manager of strategic government affairs at Dubai's economic department, said.

Dubai has argued that the EU duty on Gulf aluminium exports is discriminatory as the EU has exempted a number of countries, while others must pay the tariff. But EU officials say primary aluminium is also important for EU-based aluminium producers.

Following the latest round of free trade talks between the GCC and the EU, a European Commission spokesman said the duty remained "a difficult issue". The next session on the free trade agreement is due to be held in Brussels in June.