NEW DELHI, Dec 6 (Reuters) - Foreign donors have pledged $406 million additional funds for efforts to combat bird flu, but another $800 million is still needed and countries need to be better prepared for any pandemic, officials said on Thursday. The funds were pledged on the final day of a three-day summit in New Delhi, India, of experts on avian influenza from across the world, aimed at coordinating strategies to combat the disease. "Countries are much better prepared now than they were a year ago for a pandemic, however the preparedness is not as broad or deep as we would like it to be," David Nabarro, the United Nations influenza coordinator, told reporters. "Although some countries have tested their preparedness in exercises ... there is still more testing to be done because when the pandemic does come it will be too late to prepare," he added. (Reporting by Alistair Scrutton; Editing by Alex Richardson)