Australia's main opposition Labor Party said on Wednesday it was dropping its final objections to the passage of a landmark free trade agreement with China, clearing the last impediment to its ratification before the end of the year.

China and Australia sealed the trade agreement last year, significantly expanding ties between the world's second-largest economy and one of Washington's closest allies in Asia.

The deal, which Australia called the best ever between Beijing and a Western country, will open up Chinese markets to Australian farm exporters and the services sector while easing curbs on Chinese investment in resource-rich Australia.