Vic Labor gift card claims rejected

One of Bill Shorten's key union allies allegedly had his Labor membership paid for with an anonymous gift card linked to Victorian branch-stacking claims.

But Plumbers Union national secretary Earl Setches denies reports in The Age that he was one of 1000 members over four years who had their dues paid for by anonymous prepaid gift cards.

"I've been a member for 20 years mate. I've always had it deducted," he told AAP on Wednesday.

Mr Setches said he had "no idea" what was behind the claims.

The Age reports nearly 1000 ALP memberships and renewals over the past four years were paid for by anonymous gift cards linked to Mr Setches and Labor figure David Asmar.

Up to 100 memberships were reportedly paid for from one computer, including Mr Asmar's, while Mr Setches' 2014 membership was one of 46 paid for using prepaid gift cards in a three-hour stretch in May last year.

Labor last week suspended all internal Victorian elections until February, while an investigation into the use of prepaid cards is completed.

Mr Setches said he didn't know what had led to the reports.

"I spend about five per cent of my life in Labor party business, I run a union. I have no idea how that s*** all goes," he said.

Mr Setches said he was considering legal action against The Age over the reports.

He also said the rules around anonymous gift cards being used to pay for memberships should be tightened up.

"Everyone should be made accountable," he said.