The first of Vale's giant dry bulk vessels to arrive in China has completed delivery of its iron ore cargo, shipping data showed on Tuesday, a key step forward in the Brazilian miner's plan to cut shipping costs to its biggest market.

Reuters Freightviews and independent shipping data confirmed the 388,000-tonne vessel, Berge Everest, had departed China's Port of Dalian over the weekend for Singapore, where it will likely refuel for its journey back to Brazil.

Draught measurements indicated the ship had unloaded all or nearly all of its iron ore cargo in Dalian.

Vale has ordered 35 of the world's largest dry bulk carriers, of which six are already on the water, at an estimated cost of $4.2 billion from Chinese and Korean shipyards.

The world's second largest miner had been trying since June 2011 to get Chinese authorities to allow the megaships to enter the country's ports.

Chinese port officials have declined to comment on the arrival of Berge Everest, leaving it unclear as to whether other giant Vale ships will be allowed to dock in the country's ports.

Five other giant ships operated by Vale, the world's top iron ore producer, were not expected to follow Berge Everest into China at least in the near term.

Shipping data showed two heading back to Brazil, two in Europe and one -- the Vale Beijing -- anchored off Brazil's Ponta da Madeira Port.

The Vale Beijing, the newest member of the Valemax fleet, developed cracks in its hull on its maiden voyage, sparking concerns from Chinese shipowners about the safety of these ships.

Chinese shipowners and steelmakers are strongly opposed to Vale's vessels, fearing the ships are a Trojan Horse that the miner will use to monopolize both the shipping and iron ore markets at China's expense.

Vale, which sells about 40 percent of its ore to China, is counting on Valemaxes to slash shipping costs and better compete with Australian rivals BHP Billiton and Rio Tinto . While Vale's ore is generally of higher quality, that advantage is cancelled by Australia's proximity to China, the world's top steelmaker and biggest ore importer.

(Reporting by Randy Fabi; Editing by Himani Sarkar)