SAO PAULO (REUTERS) - Brazilian dock workers in Santos on Tuesday ended a two-day occupation of a Chinese ship to protest port modernisation plans, as unions threatened a national port strike over the government plan that they fear will cost jobs and cut wages.

About 60 stevedores boarded the Zhen Hua 10 early on Monday, stopping it from unloading cranes manufactured by the Shanghai Zhenhua Heavy Industry. The cranes are to be installed at Embraport, a new US$1.2 billion (S$1.5 billion) private container terminal in Santos that does not use established union procedures to hire workers.

Although the protest was brief, with no perceived impact on Santos port, it gave a taste of what is likely to come as unions gear up to resist a sweeping reform of port regulations. Port workers nationwide plan to walk off the job on Friday and again on Tuesday, Mr Paulo Pereira da Silva, a congressman and president of the umbrella union Forca Sindical told Reuters.

"All the ports in Brazil will be stopped at those moments," he said, adding the workers had not ruled out a prolonged strike.

The government said the planned changes are imperative to boost efficiency for its world-leading commodity export sector.

Embraport said in a statement that workers left the Chinese ship after the terminal agreed to contract unionised workers to watch over the unloading and assembly of the cranes to be carried out by representatives of the Chinese manufacturer.

Embraport denied allegations by unions that it was contracting Chinese workers as substitute dock workers, saying the unloading and assembly of the equipment by the manufacturer was pre-established in the purchase contract.