Former President Bill Clinton voiced support for a lower corporate tax rate and said the geopolitical reasoning behind the Trans-Pacific Partnership is clear.

Clinton said he supported a higher corporate tax rate in the past. Wife Hillary Clinton's presidential campaign has not released a plan that addresses the current 35 percent rate. She has also said she would put her husband in charge of reinvigorating the economy.

"I was the president who urged it to be raised to 35 percent, but when I did it, it was precisely in the middle of OECD countries. It isn't anymore," Clinton told CNBC on Tuesday on the sidelines of the Clinton Global Initiative.

"I think it should be lowered. This is just me now. I'm not speaking for," he added, trailing off without saying for whom he was not speaking.

Clinton said the United States should try to get the corporate tax rate as close to the international average as possible to make it more competitive, but it should also maintain an alternative minimum tax to ensure all businesses pay an acceptable amount.

Republican presidential nominee Donald Trump says he would drop the corporate tax rate to 15 percent.