WASHINGTON - The White House's Office of Management and Budget (OMB) is preparing for a US government shutdown if Congress does not pass a funding bill by midnight, an OMB official said on Thursday. 'The Office of Management and Budget is currently preparing for a lapse in appropriations. As we stated earlier today, we support the Bipartisan Budget Act and urge Congress to send it to the president's desk without delay,' the OMB official said.