President Barack Obama will announce an initiative on Wednesday to devote $600 million to address a central challenge of today's economy: How to train workers for skills they need for jobs that are open but hard to fill.

American companies will need 522,000 software developers and computer programmers over the next 10 years as well as nearly 110,000 pharmacists, 224,000 electricians and 941,000 customer service representatives, according to the Bureau of Labor Statistics.

To try to fill the void, Obama will announce during a visit to Oakdale, Pennsylvania, a plan to use $500 million in existing Labor Department funds to pay for a competition.

The goal of the competition is to spur employers and community colleges to work together and develop training programs that are designed to get workers prepared for specific jobs that already exist.

Another $100 million will be drawn from a Labor Department fund to support programs aimed at training apprentices in new fields with fast-growing occupations such as information technology, healthcare and advanced manufacturing.

Employers need people trained as welders, machinists, dental hygienists and even electrical power line installers, the Bureau of Labor Statistics said.

Administration officials who briefed reporters about the initiative said the aim is to address the needs of a fast-changing economy.

"The pace of change - technology, globalization - has changed the nature of work and the speed at which necessary skills change," said a senior Obama administration official.

Obama, joined by Vice President Joe Biden, is to announce the initiative at an event at Community College of Allegheny County on the outskirts of Pittsburgh.

The plan is part of an effort launched in Obama's State of the Union speech in January to act with his own presidential authority in the absence of a consensus from a divided Congress.

While the economy has rebounded since bottoming out early in Obama's first term, many Americans remain unemployed or underemployed, and Obama has made it a priority of his second term to help the middle class and reduce income inequality.