Labor leader Anthony Albanese says revelations that federal minister Bridget McKenzie oversaw funding to a shooting club of which she was a member "fails every test".

The embattled Nationals deputy leader is engulfed in a growing controversy surrounding a $100 million federal government "slush fund", which a damning audit last week revealed was used to splash cash at marginal electorates ahead of last year's federal election.

The Age and The Sydney Morning Herald revealed on Wednesday that Senator McKenzie, then sports minister, approved a $36,000 taxpayer-funded grant for a clay target shooting club in regional Victoria without publicly disclosing she was a member.

A spokeswoman for Senator McKenzie, now Agriculture Minister, said on Tuesday night that, as the Wangaratta Clay Target Club membership was a "gift" in January 2019 and valued at less than $300, a declaration to the Senate was "unnecessary".