The UK government has announced it is buying millions of doses of new Covid-19 treatment pills as the Omicron variant takes hold, while cutting the isolation period for positive cases.

The government said it has signed deals to buy 4.25 million courses of two new antiviral drugs: Pfizer's ritonavir and US rival Merck/MSD's molnupiravir, which will be available early next year, AFP reports.

This comes on top of government announcements in October of the procurement of several hundreds of thousands of doses, and was hailed as a “mammoth deal” by Health Secretary Sajid Javid.

Molnupiravir, sold as Lagevrio, is being used in a national trial run by the University of Oxford that people can join if they have virus symptoms.