[img_assist|nid=574|title=U.S. Sen. John McCain (R-Ariz.) and Former Gov. Mitt Romney (R)|desc=Getty Image|link=none|align=left|width=400|height=267]Continuing his work as a surrogate for presumptive Republican presidential nominee John McCain, former Gov. Mitt Romney (R) criticized presumptive Democratic nominee Barack Obama on Monday for his most recent television advertisement.

The Obama ad targets McCain for being too closely tied to oil companies. In particular, the ad charges that McCain has received $2 million in oil contributions that the presumptive GOP nominee plans to give oil companies $4 billion in tax breaks instead of levying taxes on their windfall profits.

"Well, that's really sad," Romney said when asked to respond on CNN's "American Morning" Monday. "I didn't know that Barack Obama had stooped to dishonesty. You know, pointing out weaknesses in other people's campaigns or positions is also fair game, but that's dishonest."

Romney went on to say that corporations don't contribute to candidates, their employees do and those employees have given to both McCain and Obama.

The former governor then refuted Obama's claim that McCain plans to give oil companies a tax break.

"John McCain doesn't ask for any tax reduction for oil companies," he said. "There's no special deal going to oil companies. He's asking to reduce taxes on all corporations to help build our economy and strengthen jobs as well as reducing taxes on individuals."

Pressed to respond to McCain's plan to cut the corporate tax rate by 10 percent, which would benefit oil companies, Romney said all corporations would benefit from the cut, not just oil companies.

"He's lowering taxes for all corporations in America to help make us more competitive with other nations of the world where corporations are going, because we have the highest corporate tax rate in the world next to Japan. So, he's trying to build our economy and create more jobs and he's not singling out any one company or another."

Ultimately, Romney said, Obama's ad is "simply dishonest as well as below the belt."

Video of the interview is below.