(Adds detail on disagreement, background)

By Valentine Hilaire

MEXICO CITY, Feb 28 (Reuters) - The Panamanian government and Canada's First Quantum are nearing an agreement on their negotiations over the contract to operate a major copper mine, Ebrahim Asvat, a lawyer advising the government on the negotiations told Reuters on Tuesday.

An agreement could be reached in less than two weeks, Asvat said, noting there are only three issues left to be solved, with two of them being in the final stage of negotiations.

Asvat said the third issue was an "economic aspect" which involved the company asking for more tax deductions that would hurt the government's income from the mine in times of high production and copper prices.

Nevertheless, Asvat said he believes "an agreement is imminent".

The company and Panama's government have been locked in a prolonged contract dispute with tax and royalties at the forefront of the stalemate.

In a latest twist, an order from Panama's maritime authority banning cargo operations at a port forced the firm to

halt its ore processing operations

. (Reporting by Valentine Hilaire; Editing by Sarah Morland)