It was a "figment of the Economic Freedom Fighters' imagination" that Treasury deputy director general Ismail Momoniat had "usurped the powers of the minister‚ the director-general and other fellow deputy director generals"‚ Treasury said in a statement on Thursday.

The department was responding to comments made by EFF chief whip Floyd Shivambu during a finance committee meeting on Tuesday. Shivambu objected to the repeated presence of Momoniat at finance committee meetings‚ saying this undermined African leadership.

He questioned why director general Dondo Mogajane or other senior officials did not attend committee meetings.

Treasury noted that the finance ministry and Treasury were required to have "thick skins" given the role they played in budget planning and processes within government and so would not normally respond to all attacks directed at them. However it was necessary in this case to respond.

"The attack on the integrity of the Ministry of Finance and National Treasury by the EFF is exceptional because of its vitriol and simply the scale of the EFF’s ignorance of the workings of the Treasury and the ministry‚" Treasury said.

"The EFF’s attacks on Treasury are based on ignorance of the policy-making function of the National Treasury (the department) and the Ministry of Finance (as the executive authority which has oversight over the department)‚ how the Treasury functions and its relationship with the Ministry of Finance.

"The EFF also displays a gross misunderstanding of parliamentary processes. Furthermore‚ the EFF has abused parliamentary privilege to throw mud at Treasury staff."

The nature of Momoniat's responsibilities meant that he was the right person to represent Treasury on all tax and financial sector policy related matters‚ said Treasury.

Treasury said that the development of policy proposals in the Treasury‚ and their ultimate approval by the minister of finance‚ was governed by clearly articulated policies and by proper governance structures.

Policy‚ regulatory‚ procurement and employment decisions were made by way of written memoranda‚ which ultimately made recommendations to the director general and/or the minister of finance and were signed off by them.

"No one person is so powerful as to make decisions over the head of the DG or minister‚" the Treasury statement said.

"Treasury prides itself on its culture of robust debate which has always been its hallmark. Those ministers of Finance who have understood and nurtured this culture have appreciated its value in ensuring that the policy decisions they eventually made were an outcome of a very robust process."

Director general Dondo Mogajane delegated powers to Treasury officials which explained Momoniat's appearance in Parliament rather than the minister or himself.

"The delegation of powers exists because it is not possible for the minister‚ or the director general to appear before parliamentary committees all the time‚" Treasury said.