Scotland’s most senior civil servant is being challenged to come to Holyrood to answer questions over the planned deposit return scheme.

MSPs, including former Scottish rural economy secretary Fergus Ewing, have challenged John-Paul Marks to seek a ministerial direction for the scheme.

Mr Ewing, now an SNP backbencher at Holyrood, said it was necessary for the Scottish Permanent Secretary to seek this explicit instruction to press ahead with the initiative – which is due to come in on August 16 – as it was “wilfully reckless”.

The scheme will see a deposit payment of 20p added to all purchases of drinks in cans or bottles, with this cash then refunded when the empty containers are returned for recycling.

I am calling on the Permanent Secretary to come before Parliament next week to answer questions from MSPs.

But businesses have raised concerns about its impact, with opposition MSPs claiming on Thursday that less than a fifth of drinks producers had signed up for it by the end of February deadline

Mr Ewing – together with Tory MSP Maurice Golden, Labour’s Claire Baker and Liam McArthur of the Scottish Liberal Democrats, – wrote to Mr Marks on February 15 in his role as “accountable officer” for the Scottish Government.

Two weeks later he said they had not received a reply, with the veteran SNP politician calling for the Permanent Secretary to come before Parliament next week to answer questions from MSPs.

In the letter the four MSPs told Mr Marks: “As the most senior civil servant in the Scottish Government we understand that you are the accountable officer.”

They added “we understand that there is a duty incumbent upon you in this role, to seek a ministerial direction” if a spending decision breaches criteria on regularity, propriety, value for money and feasibility.

Mr Ewing went on to argue that “where the Government is intent on proceeding with a policy or the implementation of a policy which is wilfully reckless” the Permanent Secretary should “seek from ministers what is called a ministerial direction”.

He added that such a direction “requires Scottish Government ministers to order him and his officials to carry out the policy, even though these officials have argued that it is in effect reckless”.

He said this was because deposit return – which is being brought in by the Scottish Government in a bid to increase recycling and reduce littering – “may be ultra vires, not value for money, not able to be implemented properly on time, and or amount to bad governance”.

In the MSPs’ letter to Mr Marks they argued all four of these applied to deposit return.

But Mr Ewing said if just any of these four grounds can be established as fact then a ministerial direction “must be sought” saying without this the “accountable officer is neglecting his clear duties”.

He added: “The fact that four MSPs from the major parties have joined together is an indication of how seriously we parliamentarians take this.

“We are working together to try to prevent a disaster from being inflicted upon small business who may close or fail.”

Mr Ewing added that he, along with the other three MSPs had given the Permanent Secretary a “fair opportunity deal with this privately first”.

But he said with no response so far and “given the gravity of the situation facing Scotland we must therefore speak out”.

Mr Ewing said: “I am calling on the Permanent Secretary to come before Parliament next week to answer questions from MSPs to explain whether he is or has issued a ministerial direction, and if not why not?

“That, surely is what democracy is about – if he is the ‘accountable officer’ – and not the ‘unaccountable officer’.”

A Scottish Government spokesperson said: “Scottish Government policy remains that Scotland’s deposit return scheme will go live on August 16.

“Civil servants serve the Government of the day with integrity and impartiality to deliver on the Government’s priorities.

“No written ministerial authority has been requested in relation to the deposit return scheme.

“The Permanent Secretary has received correspondence from Mr Ewing and other MSPs and will reply in due course.”