He said behaviour of some of the volunteers was 'completely inappropriate'

Kremer said in the video that removing campaign signs was illegal

Australian Labor Party volunteers sent to the U.S. to work on Bernie Sanders' presidential campaign have been secretly filmed stealing Donald Trump and Hilary Clinton hoardings.

Project Veritas Action, a conservative movement website who use undercover journalists to source stories, posted the video of four Australian volunteers bragging about using Australian taxpayer funds for flights, accommodation and daily expenses while working on Democratic senator Bernie Sanders' presidential campaign.

Former Australian National University Labor Club president Ben Kremer features in the 14 minute video - scrambling in the darkness of night, trying to remove Republican candidate Donald Trump's campaign signs from private property.

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Former Australian National University Labor Club president Ben Kremer features in the 14 minute video

Labor party volunteer: Ben Kremer stands next to ALP Leader Bill Shorten at a past event

F**k you Donald: Ben Kremer is secretly recorded stealing U.S. campaign signs from the front yard of a house

'Fantastic, F**k you Donald.'

'We've driven all the way out here, so we might as well try to take the big scalp,' he said in the video.

The video later records Mr Kremer openly acknowledging to the undercover journalists that removing political campaign signs from private property is illegal.

'I think it's illegal to move or like tamper with or do an anything to campaign signs,' he said.

Daily Mail Australia contacted Mr Kremer for comment.

Another labor party volunteer, identified as Rebecca Doyle, is recorded saying the ALP's 'international branch' had organised travel, accommodation and costs to assist the Sanders campaign, including $60 daily stipends.

Daily Mail Australia contacted Ms Doyle for comment.

Project Veritas Action: 'Federal election law is clear - Foreign nationals can volunteer for campaigns but they must not be compensated'

Outside Bernie Sanders New Hampshire campaign office where some Australian volunteers were based

Australian Labor Party national secretary George Wright told Fairfax Media he had launched an investigation to confirm the federal government-funded Australian Political Parties Democracy Program complied with US election laws.

He said behaviour of the four Australian volunteers was 'completely inappropriate' and would also being investigated.

Bernie Sanders' National Field Director said in the video that he was aware of the Australian's involvement in the campaign, which he said was legitimate 'as long as they are volunteering... or unless they have a work visa.'

However, the Project Veritas Action video described the Australian Labor Party volunteer's involvement as illegal.

'Federal election law is clear - Foreign nationals can volunteer for campaigns but they must not be compensated.'

Project Veritas Action's website is run by James O'Keefe, a Conservative movement filmmaker. He has produced other secretly recorded undercover video encounters of governmental and social service organisations, purportedly showing abusive or alleged illegal behavior.

Labor's Mr Wright said the volunteers had been involved in the exchange program, and they had all returned to Australia since its completion.

'They are there as observers and they should just be observing, not posting stuff on social media and certainly not doing the type of things they are depicted doing.'