OKLAHOMA CITY (AP) - Senate leaders are unveiling a revenue-neutral plan to slash the income tax by one-half of 1 percent over the next two years and pay for the cuts by eliminating and modifying numerous tax breaks and exemptions.

Flanked by the entire GOP caucus, Senate President Pro Tem Brian Bingman described the plan on Tuesday as "very responsible."

Bingman's key negotiator on tax changes, Sen. Mike Mazzei, criticized a separate proposal by the House as one that would leave a "gaping hole" in next year's budget.

The Senate plan would reduce the top income tax rate from 5.25 percent to 5 percent, beginning next year. It would further reduce the top rate to 4.75 percent in 2014.

The governor's Secretary of Finance, Preston Doerflinger, says tax cut negotiations are ongoing.