Border Force officials have been accused by their bosses of wearing fake uniforms while campaigning for a Coalition defeat in the upcoming election.

A senior Immigration Department manager issued the warning after Border Force public servants, angry about their two-year pay dispute, rallied at Sydney Airport last week to kick off their campaign to have the Turnbull government voted out.

Border Force officials have been warned not to wear fake uniforms while campaigning for a Coailition defeat in the upcoming election. Credit:Instagram

The event was the launch of a union-led campaign to put the wage dispute between Immigration and Border Force public servants and the Coalition government on the election agenda and featured unions members wearing black pants and T-shirts clearly marked with the Community and Public Sector Union's logo.