LONDON (Reuters) - Hundreds of thousands of doses of AstraZeneca vaccine have been flown to Australia from Britain but the source of the shipments was kept quiet to avoid any controversy in the United Kingdom, the Sydney Morning Herald said. The first 300,000 British-made doses landed at Sydney airport on February 28 – a month after the European Commission adopted curbs on the export of vaccines produced in the EU, the newspaper said. Another large batch arrived on an Emirates passenger plane in March, well after Italy and the European Commission formally blocked an application by AstraZeneca to ship 250,000 doses to Australia, it added. The paper cited an unidentified British official as saying the shipments to Australia were never at the expense of Britain’s vaccine rollout, one of the world’s swiftest. A spokesman for Australian Prime Minister Scott Morrison declined to comment. A second source said Australia was reluctant to confirm or deny the report. “For reasons of supply chain integrity and national security, we do not advise the origins of particular vaccine shipments,” said the source, who sought anonymity in the absence of authority to speak on the matter.