On Monday, the inquiry began four weeks of scrutiny of government decisions to purchase personal protective equipment and the use of the so-called "VIP lane" that gave priority to companies with connections, which was previously ruled unlawful by the High Court.

However, inquiry chair Baroness Heather Hallett announced in preliminary hearings for the latest module that there would be a risk of prejudice to potential criminal proceedings if "sensitive evidence" was heard in public.

Opening the latest round of hearings on Monday, Hallett said: "It is not my role, and indeed I am forbidden by the Inquiries Act, to attribute civil or criminal liability to any individual or company.

"I am aware that there are criminal or civil investigations into some of the matters that will be touched upon by this module, and in one case [related to Mone] I have agreed that some evidence will be heard with special restrictions applying to make sure I can hear the evidence without prejudicing any possible criminal investigation.

"The information that I receive [in the closed session] will become public as soon as any criminal investigations are resolved."

The inquiry heard this week that the government's 2019 expenditure on PPE had been £146 million, which was just 1 percent of the 2020 cost. In total, the government spent £14.9 billion on PPE between January 2020 and June 2022, plus a further £26 billion on track and trace measures and £700 million on ventilators.

NCA Investigation

Conservative peer Mone, 52, and her husband Doug Barrowman, 59, have faced several years of questions over the priority lane contracts granted to some suppliers during the era of COVID-19 lockdowns and restrictions.