U.S. President Barack Obama has renewed his call to boost American manufacturing and help strengthen the middle class.

Mr. Obama traveled to Asheville, North Carolina , Wednesday to promote the main themes of his State of the Union speech, which focused on proposals to strengthen the nation's fragile economy.

Speaking at a factory in Asheville, the president called for the creation of more centers for high-tech manufacturing and raising the minimum wage. He proposed working with towns and cities to attract investors, and set a national goal of training 2 million Americans with skills that will directly lead to jobs.

He said the middle class is the true engine of economic growth.

The president said the current tax code needs reform, saying it rewards companies that send jobs overseas. He said businesses should be encouraged to keep jobs in the United States.

He called on Congress to take up the initiatives.

In his State of the Union speech Tuesday, President Obama emphasized the importance of creating new jobs.

The president warned that the automatic spending cuts set to take effect if Congress cannot reach a budget deal will jeopardize military readiness, slow economic growth and devastate priorities like education, energy and medical research.

Mr. Obama also urged Congress to pass legislation on two issues currently under debate on Capitol Hill - gun control and immigration reform.

In the Republican Party response, Senator Marco Rubio said the "free enterprise economy" is the source of middle class prosperity. He accused President Obama of believing it is the cause of the country's economic woes.