Pictures of cabinet minister Simon Birmingham visiting a trades training school with Bob Day six months before the school received a controversial $2 million grant from the federal government have sparked claims by Labor that Senator Birmingham misled the Senate and should resign.

The pictures, taken in May 2015, have placed a question mark over Senator Birmingham's explanation at a recent Senate hearing about his depth of knowledge of the former Family First senator's involvement in the North East Vocational College in suburban Adelaide.

As questions began to mount about the $2 million grant to the college, Senator Birmingham was asked at an estimates hearing on October 20 whether he knew Mr Day was a director of North East Vocational before public money was ploughed into the college to fund the crossbencher's pet project, a pilot program known as "student builders".

Senator Birmingham responded: "I know that Senator Day knew of the North East Vocational College. I cannot say that I recall that he had any role in it, but that is not to say that I had not been told that at some stage."

But four photos posted on North East Vocational's Facebook page in May 2015 – a month before Mr Day met Senator Birmingham in the minister's Canberra office to pitch for funding for his pilot program – suggest Mr Day had not kept his hands-on role, which included 10 years as chairman, with the college at all secret.

Tagged "Senators Birmingham & Day visit NEVC", the pictures show the pair meeting students and college staff at the small St Agnes campus of the school in northern Adelaide.

Labor's Doug Cameron, who has been pursuing the apprenticeships grants matter in Parliament, said the emergence of the pictures calls into question Senator Birmingham's version of events.

"He has deliberately misled the Senate; there's absolutely no way that his response reflects the reality of the situation," Senator Cameron said.

"Bob Day was a very important and quite fundamental political player at the time. Simon Birmingham is trying to cover up what is a misuse of public money in return for Bob Day's support in the Senate.

"If Simon Birmingham had any credibility he would resign and if he won't resign, the Prime Minister should take action."

In a statement, Mr Birmingham said: "My department advised former senator Day has no financial interest in NEVC and they were one of many educators and organisations I met with to work out how best to tackle the mess that Doug Cameron and Labor created in Australia's apprenticeship system, with $1.2 billion worth of cuts and the largest single drop in apprenticeship commencements on record.

"As I said at Senate estimates, when I was the assistant minister responsible for vocational education and training, I visited many, many training facilities to see the great work they do.

"Mr Day was as entitled as any other member of Parliament to advocate on behalf of community organisations in his electorate. This is a well-regarded training organisation that just the other day had the South Australian state Labor treasurer visit it too."

Earlier in the estimates hearing, Senator Birmingham, who is now Education Minister, said he had toured North East Vocational in the first half of 2015 in his then capacity as assistant minister for vocational education and training but did not mention Mr Day's presence.

"It was a site visit. I was invited to go and visit their training facility," he said.

Senator Cameron then asked: "Who did you meet when you met with the North East Vocational College?"

"I would have to go back and check," Senator Birmingham replied. "I simply do not remember the names of the people who run the North East Vocational College. Obviously, they were present at the time I visited their training facility."

Subho Banerjee, deputy secretary of the Department of Education and Training, then clarified that the department knew of Mr Day's long-standing involvement with the college and had informed the minister.

It was Senator Birmingham's successor as assistant minister, Luke Hartsuyker, who awarded the $1.84 million grant to North East Vocational in December to trial Mr Day's pilot program with 20 builder's apprentices at the campus.

Documents obtained under freedom of information reveal Mr Day's proposal was effectively triple-dipping for funding through the $1.84 million grant, asking students to also take out VET-FEE HELP loans to cover the cost of their education and charging employers to use apprentices in training.

Neither the college, Assistant Minister for Vocational Education and Skills Karen Andrews, or Mr Day have been able to explain what the $1.84 million grant was going to be spent on.

A two-page ministerial briefing document and a 20-minute presentation to the Apprentices Reform Advisory Group appear to be the only documents supporting Mr Day's application for the grant.

Just three groups were allowed to present to the advisory group – Mr Day on behalf of North East Vocational, Master Builders Australia, and the National Electricians and Communications Association – all strident supporters of the Coalition's plan to reintroduce the Australian Building and Construction Commission.

Jenny Lambert, advisory group member and acting chief executive of the Australian Chamber of Commerce and Industry, said the panel of experts was not asked to give its advice on any of the pilot projects approved by the government.

"I do remember Bob Day making a presentation, but the panel made no recommendations about the specific pilot," she said.

Three months after the advisory panel made general recommendations about the merit in looking at alternative pathways for apprentices, all three groups were given $1.84 million without any competitive tender process.

The NSW executive director of Master Builders Australia, Brian Seidler, said the money would be used to support hundreds of apprentices in low socioeconomic areas.

"You would think that the funding would be there to fund at least something," said Mr Seidler.

"For us, funds were split up based on how many apprentices you can get into a position, be mentored and spread across Australia in areas like western Sydney."

The allocation to North East Vocational equates to $90,000 for each of the 20 apprentices taking part in the pilot, compared with the $3000 per year it costs at TAFE to educate an apprentice.

The grant doubled the annual income of North East Vocational overnight.

Mr Day had originally asked for $1.4 million for the pilot but the grant received from government was almost $500,000 more than his request.

The government later called on a "stream 2" consultation with training providers to pitch for similar grants. It received 29 submissions but none were able to brief the advisory group because it had already reported.

In a text message, Mr Day would say only "We're all volunteers" of his role at North East Vocational.

Later, Labor Senate leader Penny Wong accused Mr Birmingham of providing a "classic lawyer's answer" to the hearing.

"I'm a lawyer so I can say that. It was classic answer that you give if someone is trying to avoid answering the question. We've got a lot of taxpayers' money involved. We've got some pretty unusual circumstances, advice against funding this college, the college being funded for more than it asked for and being funded almost the equivalent of its entire budget ... this grant was actually more than the college's entire revenue for the previous year," she said.

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