WASHINGTON — German Chancellor Angela Merkel urged Congress Tuesday to take dramatic action to stop climate change, but the political difficulties were evident as Republicans boycotted a Senate committee meeting to consider changes to a climate change bill.

"We cannot afford missing the objectives in climate protection," Merkel said at a joint session of Congress. "The world will look to us, to the Europeans and to the Americans."

But Republicans shunned the Environment and Public Works Committee meeting to protest committee Chairwoman Sen. Barbara Boxer's refusal to order a full new analysis of the legislation.

Boxer, D-Calif.argued that the Environmental Protection Agency's existing analysis, based on a similar bill passed by the House of Representatives in June, is sufficient. Republicans rejected that logic.

"I don't recall finding meaningful solutions with incomplete information and stark partisanship," said Sen. George Voinovich, R-Ohio.