A 46-year-old man has been arrested as part of the National Crime Agency (NCA) investigation into PPE Medpro.
The suspect, from Barnet, north London, was held at his home on Wednesday morning, the NCA said.
It is carrying out an investigation into suspected criminal offences in the procurement of PPE contracts by PPE Medpro.
Baroness Michelle Mone, 52, and her husband Doug Barrowman, 59, have faced controversy over the so-called “VIP lane” contracts granted to some suppliers during the coronavirus pandemic.
PPE Medpro, a consortium led by Mr Barrowman, was awarded Government contracts worth more than £200 million to supply personal protective equipment after Lady Mone recommended it to ministers.
The Department of Health and Social Care (DHSC) has since issued breach of contract proceedings over the 2020 deal on the supply of gowns.
Both Lady Mone and Mr Barrowman deny any wrongdoing.
Subscribe or register today to discover more from DonegalLive.ie
Buy the e-paper of the Donegal Democrat, Donegal People's Press, Donegal Post and Inish Times here for instant access to Donegal's premier news titles.
Keep up with the latest news from Donegal with our daily newsletter featuring the most important stories of the day delivered to your inbox every evening at 5pm.