House Speaker Paul Ryan asserted on Thursday that Congress "really can" get a tax overhaul done this year.

The process behind crafting tax reform was quite different than the separate House and Senate approaches to the failed efforts to repeal Obamacare, said Ryan, who appeared on CNBC's "Squawk Box" a day after GOP leaders unveiled a framework for tax reform.

"We really can get this done this year," the Wisconsin Republican said. "You're not going to get 3 percent [economic] growth in 2018 if you don't get this done in 2017. So we're really serious about that."

The deal President Donald Trump struck with Democrats extending the debt limit authority and government funding until December gives the "time and space" for tax reform, Ryan said.

"Instead of having some possible government shutdown issue on the floor next week, we've got the budget on the floor next week, which gets us tax reform," Ryan said.

"There is not another thing we can do in Congress ... that will do more to grow this economy, lift wages, help people get a raise ... than doing tax reform. This is it. This is the game changer for our economy," he added.

The Republican proposal calls for cutting personal and corporate tax rates and aims to simplify the tax code.

Provisions include collapsing the current seven personal tax brackets to just three: 12, 25, and 35 percent and nearly doubling the standard deduction.

"Our framework includes the explicit commitment that tax reform will protect the low-income and middle-income households. Not the wealthy and well-connected," Ryan said.

The House speaker echoed remarks from Trump economic advisor Gary Cohn, who told CNBC earlier Thursday that "we're doing an awful lot to help hard-working Americans."

"We took the 15 percent tax rate and lowered it to 12," Cohn said. "So if you look at that in its entirety, we have really helped out lower income earners."

On the corporate side, the GOP plan calls for lowering the corporate rate from 35 to 20 percent, and bringing down the rate for so-called pass-through businesses from 39.6 percent to 25 percent.

Nonpublic pass-through businesses — such as sole proprietors, limited liability companies and partnerships — pay no income tax themselves. Instead their profits "pass through" directly to their owners, who pay tax on them at the individual tax rates.

Ryan was one of the "Big Six" officials who crafted the GOP proposal. The others were Cohn, Treasury Secretary Steven Mnuchin, House Ways and Means Chairman Kevin Brady, Senate Majority Leader Mitch McConnell and Senate Finance Chairman Orrin Hatch.

Cohn, formerly the No. 2 executive at Goldman Sachs, also told CNBC the GOP tax cuts will be paid for entirely through economic growth. The director of the National Economic Council also said there's "no room to negotiate" the proposed 20 percent corporate tax rate.

Ryan said: "We are just as committed as the White House is to holding" the 20 percent rate on corporate taxes.

— Reuters contributed to this report.