"The sign at the moment is positive but we're not there yet in saying this is 100% going to work," Argar told Talk Radio.

"We are continuing to research at pace... We are making very good progress now and I am hopeful we will see some positive news on that front."

An antibody test works by looking for signs of immunity generated when someone has had the virus. There has been speculation that successful antibody tests could prove decisive in determining who is allowed to return to work or move out from under other lockdown restrictions.