ATHENS, July 16, 2008 (AFP) - Commercial activity at Greece's main port ground to a halt Wednesday as dockworkers began a two-day strike to protest against the privatisation of the main container terminal at Piraeus.

A union of dockworkers at Athens' chief port prevented cargo from being loaded or unloaded in three zones, a union official told AFP.

But he said passenger traffic was unhampered during the busy tourist season.

The workers are protesting against the planned privatisation of the main container terminal which appears set to be taken over by China's giant Cosco group.

Cosco Pacific Ltd. has been tipped as the winner at Piraeus with what the port authority (OLP) described as a high bid of 4.31 billion euros (6.8 billion dollars) for the 35-year concession.

It has also pledged investments of 620 million euros.

The second highest offer came from a consortium led by the Hong Kong-based Hutchison Port Holdings (HPH) for about four billion euros and investments of 354 million euros.

The Greek government early this year unveiled plans to partially privatise container terminals at Piraeus and Salonika.