White House economic adviser Gary Cohn on Thursday said the administration now expects U.S. economic growth to be "substantially" higher than 3 percent, saying the boost would pay for Republicans' tax plan.

"We think we can pay for the entire tax cut through growth over the cycle," Cohn told CNBC.

"Our plan was based on a 3 percent GDP growth. We think we can now be substantially above 3 percent GDP growth," citing the administration's plans on deregulation and tax reform. 

"We think we can drive a lot of business back to America, we can drive jobs back to America, we can make ourselves very competitive," Cohn told CNBC.

Cohn said the cuts won't increase the budget deficit.

Lowering the rate will make the U.S. more competitive for development globally, which in turn will drive productivity, wages and employment that will get growth above its sluggish postrecession trend, CNBC reported.

"All of these things lead to higher GDP," he said. "We think this is very attainable."

Cohn said the provision to double the standard deduction will reduce taxes for working families, CNBC explained.

"We have to give everyday hard-working Americans a tax cut," he said. "This has to be good for American workers, it has to be good for everyday American citizens. If we don't do that, we haven't accomplished anything."