Serious differences remain as U.S. "fiscal cliff," talks drag on

U.S. House Speaker John Boehner (R-OH) speaks to the media outside his office on Capitol Hill in Washington, December 7, 2012. REUTERS/Yuri Gripas

WASHINGTON (Reuters) - Sharp differences remained on Wednesday between congressional Republicans and the White House in talks to avert the "fiscal cliff" of steep tax hikes and budget cuts, and negotiators warned the showdown could drag on past Christmas.

Both sides refused to give any ground in public, one day after what U.S. House of Representatives Speaker John Boehner described as a "frank" conversation with President Barack Obama about the remaining hurdles to a deal.