Britain approved on Thursday Valneva's COVID-19 vaccine, making it the first European country to give a nod to the French firm's coronavirus shot, that is easier to store and involves a process widely used in making flu and polio vaccines.

The shot is also the sixth COVID-19 vaccine to be approved in the UK, whose government had in September scrapped a 1.4 billion euro supply deal.

Euronext temporarily halted trading in Valneva's shares, that were indicated sharply up. At Wednesday's closing price of 15.255 euros, they are down 37.7% since the start of year after gaining 216% in 2021 and 202% in 2020

"It is also the first, whole-virus inactivated COVID-19 vaccine to gain regulatory approval in the UK," the UK health watchdog said in a statement, adding the shot met required safety, quality and effectiveness standards.

In vaccines such as Valneva's VLA2001, the virus is grown in a lab and then made completely inactive so that it cannot infect cells or replicate in the body but can still trigger an immune response. It is seen by some as having the potential to win over people wary of some which use new mRNA technology.

Rx Securities' managing director Samir Devani said even after the mass roll-out, Valneva's vaccine could still be useful if a new variant arises.

"The fact that it is available on hand is good news, although the exact revenue profile beyond the orders already received from the EU and Bahrain remains unclear," he said.

Devani said the approval bodes well for the decision from the EU's human medicines committee (CHMP), which is assessing the drug after the European Commission signed an advance deal for up to 60 million doses.

Valneva has said in March it expected a positive EMA recommendation this month and that it had begun manufacturing and has inventory ready for labelling and deployment once it is is approved there.

Bahrain granted Valneva's vaccine emergency use authorisation in early March.

Earlier this year, analysts at Jefferies estimated 4 to 5.5 billion COVID-19 vaccine doses will be delivered globally this year, mostly outside the European Union and United States, which have received the lion's share of supplies.

VLA2001's storage temperature is similar to that of a domestic refrigerator, making it appropriate in countries where storage at very low temperatures is a challenge.