Health Secretary Matt Hancock will give evidence to the inquiry into the infected blood scandal on Friday afternoon.
Mr Hancock is due to appear before the Infected Blood Inquiry and is expected to be quizzed about compensation and support for those affected by the scandal.
The inquiry is examining how thousands of patients were infected with HIV and hepatitis C through contaminated blood products in the 1970s and 1980s.
About 2,400 people died in what has been labelled the worst treatment disaster in the history of the NHS.
“However, our clients are hoping he will also provide details of the independent reviewer’s appointment, whose role is to manage a new compensation framework, as promised back in March and about which we have heard nothing since.
“Understandably, Mr Hancock and colleagues have primarily focused on Covid of late.
“However, infected blood remains the biggest treatment disaster in the history of the NHS, having begun decades ago yet the effects are on-going and raw.
“We urge the Government not to lose sight of its obligations to all those who have suffered and those who continue to do so by putting the matter of fair recompense to bed, once and for all.”
Mr Collins said he hoped other key decision makers including former prime ministers will agree to give evidence to the inquiry.
He added: “We need all those involved in leading the effort to protect this nation’s health over the past few decades to come together to achieve justice for those affected.
“We remain hopeful that those with responsibility for past decisions such as Lord Fowler, Lord Clarke, Edwina Currie, Baroness Bottomley, Stephen Dorrell, Alan Milburn, Lord Reid, Patricia Hewitt, Alan Johnson, Andy Burnham, Lord Lansley and Jeremy Hunt as well former PMs from Major to May, and those in between, will similarly be called and agree to participate.
“Their recollection of events is crucial to help us understand how this scandal came about, the response and how a recurrence can be prevented.”
Mr Hancock’s appearance comes after Scotland’s Public Health Minister Mairi Gougeon told the inquiry on Tuesday that the UK Government will need to compensate those affected by the infected blood scandal.
When asked whether it was inevitable that the Government will need to provide “substantial compensation” to these infected and affected, the MSP said: “Yes.”
It was announced on Thursday that Sir Robert Francis QC, who chaired the public inquiry into the scandal at Mid Staffordshire NHS Foundation Trust, had been appointed to carry out a study into options for a framework for compensation.
Mr Collins said: “I know my clients will welcome the appointment of such a respected medical law professional to undertake the sensitive task of establishing a fair and far-reaching compensation framework.
“We anticipate this move will finally help ease the suffering of so many people arising from the biggest treatment disaster in NHS history.”
The Infected Blood Inquiry is being led by former High Court judge Sir Brian Langstaff.
Two previous inquiries have been branded a whitewash by campaigners.
Previous witness hearings, which featured harrowing testimony from victims and their families, have taken place in London, Belfast, Leeds, Edinburgh and Cardiff.