Could the EU's vaccines spat impact the UK's supply?

In the last 24 hours, the EU has threatened to place export controls on vaccines manufactured in the EU; while a German paper has been corrected by Berlin for misreporting that the German government thought the Oxford-Astrazeneca jab was only eight per cent effective in over-65s. Isabel Hardman talks to Katy Balls and James Forsyth about what's going on and whether it could impact Britain's supply.