A man who lost his father during the coronavirus pandemic said it was vital ministers' Whatsapp messages were handed over to the Covid inquiry.
Leamington Spa resident Lobby Akinnola claimed that the government appeared to be concealing something by being reluctant to provide all the information.
The government has so far refused to release some messages, arguing it must protect the privacy of ministers.
Mr Akinola said: "It doesn't make sense to just get half of the information. ".
Former Prime Minister Boris Johnson has said he will hand over unredacted messages dating back to May 2021 but the Cabinet Office is planning to try and block the inquiry's request.
Inquiry chair Baroness Hallett is due to give a response on Tuesday.
Mr Akinnola's father, Femi, died with Covid-19 in April 2020 at the age of 60.
He was a regular gym-goer, with no underlying health conditions, and Mr Akinnola said he thought racial inequalities may have put him at greater risk.
He said: "I'm just hoping [Baroness Hallett] maintains and upholds this commitment to getting the information we need to find out how we ended up here. ".
He said he wanted to know if lessons could be learnt from the government's handling of the pandemic and said the WhatsApp messages were "vital" to understanding how it made its decisions.
Mr Akinnola said he understood people had a right to privacy but "if they're using WhatsApp to conduct public business, the business of government, then it makes sense that this is handed over. ".
The campaigner said the government should be able to trust the "decorated, experienced judge" and added: "It does feel there's something bigger going on that the government is trying to keep back. ".
The Cabinet Office has said it would seek a judicial review of the inquiry's demand that it submit Boris Johnson's WhatsApp messages unredacted.
It said it would not send information that is "unambiguously irrelevant" to the inquiry.
