Europe's medicine regulator has warned countries not to go it alone with single-dose injections as pressure builds on governments to speed up vaccination. The European Medicines Agency said on Monday the maximum interval should be 42 days between the first and the second dose of the Pfizer-BioNtech vaccine. Evidence of the vaccine's efficacy is based on a study where doses were administered 19 to 42 days apart, the agency said. It said that full protection came seven days after the booster. "Any change to this would require a variation to the marketing authorisation as well as more clinical data to support such a change, otherwise it would be considered as 'off-label use'," the agency said. Europe is battling to catch up in the vaccine race as authorities face criticism for being slow. Denmark became the latest country to follow a British initiative to stretch the interlude between doses to maximise the number of people receiving the initial injection. Talks on approving the Moderna vaccine were brought forward to Monday. The European Commission was forced to defend its strategy after being accused of failing to deliver enough doses. Member states have complained that Europe’s Covid-19 response has been far too slow compared to those of Britain and the US. They have pushed through emergency authorisation of two vaccines. Last week, French President Emmanuel Macron said he would “not let an unjustified slowness take hold”. The first doses of the AstraZeneca-University of Oxford vaccine were administered in England on Monday. The UK has ordered about 100 million doses of that vaccine, enough to give 50 million people the two shots required, and last month Britain became the first country to use the Pfizer-BioNTech inoculation. In Finland, health authorities were reportedly unhappy that about 40,000 doses were received in December, instead of the 300,000 expected. European Commission spokesman Eric Mamer said the main problem with distribution “is an issue of production capacity, an issue that everybody is facing". “We have actually signed contracts that would allow member states access to two billion doses, largely enough to vaccinate the whole of the EU population," Mr Mamer said. As part of its strategy, the EU has sealed six vaccine contracts, with Moderna, AstraZeneca, Sanofi-GSK, Pfizer/BioNTech, Janssen Pharmaceutica and CureVac. Only the Pfizer/BioNTech vaccine, which has to be stored at ultra-low temperatures, has been approved for use so far in the 27-nation EU. The European Medicine Agency said its human medicine committee was meeting on Monday “to discuss the Moderna vaccine”. The Agency in Amsterdam had been scheduled to discuss authorising the Pfizer-BioNTech vaccine for use on Wednesday. “The meeting scheduled for Wednesday, January 6, is also still planned in case the committee does not reach a decision today,” the agency said. Mr Mamer also clarified the role of the commission in securing contracts with drug makers. He said the body did not buy doses of vaccines directly but “acted as an investor" to provide funding to pharmaceutical companies involved in their development. The goal was to speed up research and production capacity, with each EU nation free to decide how many doses it would buy from the makers of its choice. “Ultimately, these vaccines have to be produced, delivered, and some of the logistic chains involved are very sophisticated," Mr Mamer said. Major deliveries of doses were anticipated by April, he said. Asked why the European Commission did not buy more doses of the Pfizer-BioNTech vaccine, health policy spokesman Stefan de Keersmaecker said the “main philosophy was to diversify our portfolio, not to put all our eggs in one basket". Mr de Keersmaecker said the contract with Moderna was for an initial purchase of 80 million doses on behalf of all EU nations, but the commission intends to double that when the vaccine is approved. It has an option for another 100 million Pfizer-BioNTech doses that will bring the total to 300 million, he said. Last week, the agency said EU approval of the AstraZeneca-Oxford vaccine in the next month was unlikely.