Lawmakers and lobbyists were urging the White House on Monday to freeze the implementation of proposed regulations prohibiting online gambling after the banking industry said the rules were ambiguous and unworkable.

Barney Frank, the Democratic chairman of the House financial services committee, said he was “deeply disappointed” that the Bush administration was moving forward with so-called midnight rulemaking that would burden the financial industry at a time of economic crisis and tie the hands of Barack Obama, the incoming president.