The CEO of LinkedIn shares the No. 1 job skill American employees are lacking

As businesses increasingly rely on cross-company collaboration, they are placing a heavier emphasis on interpersonal communications. Unfortunately, this is a job skill that many American employees are lacking, according to LinkedIn CEO Jeff Weiner.

In newly published research, the company analyzed skills shortages based on data from member profiles and job postings across 100 major U.S. cities.

"Somewhat surprisingly ... interpersonal skills is where we're seeing the biggest imbalance," Weiner told CNBC's "Squawk Box" in April. "Communications is the No. 1 skills gap across those major cities in the United States."

However, this skill is critical, especially in jobs like sales development and project management, the CEO said.

LinkedIn's latest findings support a 2016 study published in the Journal of Education, which found that managers pay special attention to communication skills and analytical skills when evaluating an employee.

The job platform Monster also found that the ability to communicate effectively is one of the most in-demand "soft skills," according to an analysis of some 940,000 job listings.

"Master communicators have solid listening skills, the ability to tune into a person with focus and the ability to articulate clearly," says Cheryl Cran, a management coach and author of "The Art of Change Leadership."

"As technology continues to infiltrate how we work, our human interaction skills need to be upgraded," she says.

Even billionaire entrepreneur Richard Branson stresses the importance of developing solid interpersonal skills at the start of your career. "The most important skills I had to learn to be successful were people skills," he tells CNBC Make It.

Branson shared this advice with fellow entrepreneur Elon Musk, years before Musk founded SpaceX and Tesla.

In his autobiography "Finding My Virginity," he recalls telling Musk, "If you don't have your own ventures one day, you're welcome to come and run one of mine — just brush up on your people skills."

Perhaps unsurprisingly, LinkedIn's research found a skills shortage particularly among software engineers and other advanced tech jobs, Weiner said on "Squawk Box."

The data showed that communication isn't the only pain point for workers. It also found a lack of basic digital fluency, like the ability to use a spreadsheet, which is a critical skill in the ever-evolving job market.

"If you are displaced or the needs of your job and your company have changed," said Weiner, "you're in a much better position to re-skill and learn new jobs when you already have that strong foundation in place."

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