Republican Party 2012 vice presidential nominee-designate U.S. Rep. Paul Ryan, R-Wis., said he will release two years of his U.S./state income tax returns, according to an interview on CBS's "60 Minutes," Reuters reported.

Mitt Romney -- a former private equity executive with an estimated net worth of roughly $250 million -- has refused to publicly release more than two years of tax returns.

Polls show U.S. President Barack Obama has benefited from putting Romney on the defensive over his taxes and wealth, painting him as someone out of touch with middle-class Americans.

Romney campaign officials declined to comment about the vetting process and how many years of tax returns were required, saying it was meant to be "private and confidential."