US president-elect Barack Obama today called for urgent action to stem the country's economic decline, lending his backing to a 825-billion-dollar stimulus package introduced by lawmakers a day earlier, according to DPA. But Obama warned that even with a massive injection of public cash into the world's largest economy "things could get worse before they get better." "I want everybody to be realistic about this," Obama said in a speech at a factory in Ohio. Democratic leaders in the House of Representatives yesterday unveiled the details of the 825-billion-dollar stimulus, which includes 550 billion dollars in public spending and 225 billion dollars in tax relief. Obama, who takes office next Tuesday, said the year-long recession in the US was "unlike any we've seen in our lifetime".