House Speaker Paul Ryan defended his reputation as a deficit hawk Tuesday despite his recent support for tax cuts and spending hikes, saying that he still favors major entitlement reforms.

"Over the long term horizon, we’ve got to get this debt under control and the only way to do that is entitlement reform," Ryan said in an interview on Fox Business. "That’s why we’re never going to give up on entitlement reform."

Ryan was forced to defend his fiscal bona fides after host Maria Bartiromo challenged him for first passing a major tax cut and then agreeing to a deal to increase spending over the next two years.

"I still am" a deficit hawk, Ryan said. The spending deal was necessary to fund the military, he argued, and the tax cut was needed to keep companies from leaving the U.S. because of its tax system.

The underlying problems driving the mounting debt, he said, are the aging of the country and rising healthcare costs.

"Social Security is a part of a solvency problem ... but nothing like we do on the healthcare entitlements," he said. "That’s why we can never give up on healthcare reform, because that is the key driver of our debt in the future."

Last year, House Republicans passed a bill to replace Obamacare and revamp Medicaid, but the Senate did not do the same. Senate Majority Leader Mitch McConnell has signaled that a big entitlement reform effort won't be in the works this year either.

Ryan rose within the House Republican ranks by authoring budgets that called for major reforms to Medicare in order to balance the budget, giving recipients premium support to buy private insurance.