Clinton said in a speech Monday that Obama may have spoken out against the U.S.-led invasion of Iraq in 2002, but had done nothing to hasten an end to the ongoing occupation since he joined the Senate in 2005.

"Words can be powerful, but only if the speaker translates them into action and solutions," Clinton told the audience at George Washington University.

The former First Lady also chided Republican front-runner John McCain for his memorable remarks that the United States could be in Iraq for 100 years.

The Obama and McCain camps fired back, Washington newspaper The Hill said Tuesday. Obama's team reminded Clinton voted in favor of the invasion. McCain's people said the 100-year remark has been repeatedly taken out of context and challenged Clinton to debate the issue.