One of Victoria's most prominent union leaders has been hit with legal action over a two-week picket line blockading millions of dollars of pre-Christmas cargo on the Melbourne waterfront.

The dockside picket line, which received a mass show of support from several unions on Friday, has been stopping freight trucks from accessing more than 1000 stranded shipping containers carrying Christmas retail goods, Christmas decorations, fresh food and medicine.

Luke Hilakari is secretary of the Victorian Trades Hall Council. Credit:Pat Scala

International stevedore Victoria International Container Terminal (VICT) has previously won orders in the state's Supreme Court for the maritime union to lift the illegal picket line.

However, the campaign has since been taken up by the wider union movement, which has continued manning the controversial blockade.