Dominic Cummings has failed to provide evidence to substantiate his allegations that senior cabinet ministers mishandled the coronavirus pandemic that he had promised to provide to a parliamentary inquiry.

Critics of the government were waiting to see what documents the former political adviser to Boris Johnson had collected during his time in Downing Street.

Cummings, who last November left his post as No 10’s most senior aide, two weeks ago faced senior MPs on two Commons committees who are conducting an investigation into lessons learned from the Covid outbreak, given the independent inquiry promised by the government is not due to start until next spring.

Cummings promised to hand over further written information to substantiate several claims, including that the former cabinet secretary, Mark Sedwill, told Johnson in mid-April 2020 that he had “lost confidence” in the “honesty” of the health secretary, Matt Hancock.

Asked if he made a note of that conversation at the time, Cummings said yes and agreed to supply it to the committee.

Allies of Cummings have privately cast doubt on how much physical evidence he had, saying many of the conversations that he recounted – to demonstrate what he saw as the government’s chaotic and inept handling of the pandemic – were quick face-to-face discussions that were not minuted.

More than 10 days after his six-hour testimony in parliament, the chair of the health and social care select committee, Jeremy Hunt, confirmed that he had received nothing new.

Asked if Cummings had provided further evidence, Hunt said: “No he has not … We haven’t received the written evidence to back those claims up that we were expecting.”

Hunt said Cummings “made some very serious allegations” against Hancock and promised to put those claims to the health secretary, when he faces the same committees on Thursday, “to give him his rightful chance to respond”.

A friend of Hancock’s said that he would try to avoid being dragged into Cummings’ accusations when he gives evidence later this week and would not “play his game by his rules”, instead “focusing on delivery” and “turning down the temperature of the situation”.

Questions to be put to the health secretary in the hours-long evidence session on Thursday were expected to include how and when decisions about the first, second and third national lockdowns in England were made, the government’s pandemic preparedness, the impact of the Delta variant discovered in India and Johnson’s roadmap.