US President Barack Obama has officially declared the floods caused by tropical Storm Irene in North Carolina and New York, a disaster. The move allows the two states to tap federal funds for relief efforts.However, the declaration did not include Vermont, which suffered its worst flooding in decades. About 40 people were killed by the storm, which also caused damage estimated at more than 10 billion dollar and forced a shutdown of New York City. Millions of people on the east coast of the country are still without power after Irene, which made landfall in the US on Saturday.