CEOs across the globe are sitting on "magic mountains" of cash and not reinvesting it into the economy, according to the Philip Jennings, general secretary of labor union UNI Global, who warned that it risks creating dangerous asset bubbles.
"The prospects for global growth look better. We have an investment strike that's taking place. I don't know what's happened to the animal spirits of contemporary business people and entrepreneurs. They are sitting on trillions of dollars," he said.
"It's sitting in the bank, doing nothing, inflating the next asset bubble."
Jennings was thankful that the key themes at the World Economic Forum were inequality and social tension but added that it was time for these concerns to "capture the minds" of business leaders at the Davos event.
(Read More: Bill Gates: No poor countries by 2035)
He said that business leaders were not putting "their money to work" due to concerns about growth.
"The CEO - Davos man - is sitting on a 'magic mountain' pile of money and they are not putting it to work," he said.
UNI Global Union is based in Nyon, Switzerland and represents more than 20 million workers from over 900 trade unions, according to its website. It specializes in the skills and services sectors.
Jennings reacted specifically to the ILO Global Employment Trends 2014 report released this week. The report said global unemployment increased by 5 million people in 2013 and predicted it would rise by a further 13 million people by 2018, on current trends.
"Business has ruptured the contact with the working population...it's twisted out of shape in a number of regards" Jennings said.
(Read More: Pope urges Davos elite to serve humanity with wealth)
Meanwhile, Pope Francis on Tuesday challenged business leaders assembled at Davos to put their wealth at the service of humanity.
"I ask you to ensure that humanity is served by wealth and not ruled by it," Pope Francis said in an official message read out at the opening ceremony.
The pontiff urged business leaders to not leave most of the world's population in poverty and insecurity and to promote inclusive prosperity instead.
By CNBC.com's Matt Clinch. Follow him on Twitter