President Obama signed a bill today designed to encourage investment in start-up businesses -- and also appeared to respond to Republican criticism that he promotes too much government involvement in the economy.

"I've always said that the true engine of job creation in this country is the private sector, not the government," Obama said during a signing ceremony in the White House Rose Garden. "Our job is to help our companies grow and hire."

Obama said that's why he pushed for the bipartisan Jump-start Our Business Start-ups (JOBS) Act that he signed Thursday.

"That's why I've cut taxes for small businesses over 17 times," Obama said. "That's why every day I'm fighting to make sure America is the best place on Earth to do business."

House Minority Leader Eric Cantor, R-Va., a frequent critic of the president, helped sponsor the JOBS Act, and attended the White House ceremony.

Afterward, he also called for more tax cuts to help small businesses.

"This month, the House will vote on the Small Business Tax Cut, a 20 percent tax cut that will provide real relief to more than 22 million small businesses in our country," Cantor said.

The bill signed Thursday will make it easier for business owners to take their companies public, Obama said. It also removes regulatory barriers to investment in start-ups and small businesses.

"For the first time ordinary Americans will be able to go online and invest in entrepreneurs that they believe in," Obama said. "Of course, to make sure Americans don't get taken advantage of, the websites where folks will go to fund all these start-ups and small businesses will be subject to rigorous oversight."