An aide in the U.S. Senate announced today, Thursday, that Senate leaders have agreed to increase the borrowing limit for the Treasury Department by $480 billion. The aide added that this amount is what the Treasury Department stated is necessary to extend the debt ceiling until December 3. The federal debt ceiling is the legally imposed maximum amount of public debt the United States can incur, which is set at $28.4 trillion. According to the U.S. Treasury, this limit will be reached on October 18. Senate Majority Leader Chuck Schumer warned on Tuesday that if Congress does not raise the federal debt ceiling and the risk of the United States defaulting on its debts remains, credit rating agencies may "very soon" downgrade U.S. debt ratings.