Britain's King Charles met with U.S. tech leaders on Tuesday as part of his four-day state visit to the United States. The pair discussed the challenges faced by early-stage startups, as the UK strives to establish itself as a desirable destination for technology companies.

Technology leaders Charles met include Amazon founder Jeff Bezos, Apple CEO Tim Cook, Nvidia CEO Jen-Hsun Huang, AMD CEO Lisa Su, Salesforce CEO Marc Benioff and Alphabet President Ruth Porat.

Charles points to the problems faced by companies that are spun out of university research and the difficulty these start-ups have in accessing funding. “I’ve always believed that these are the companies that have the hardest time getting started,” he told the CEOs. “They fall into the terrible ‘Valley of Death.’”

Huang pointed to the huge opportunities in areas such as artificial intelligence and quantum robotics: "What we need is a vibrant venture capital ecosystem and entrepreneurial culture," he told Charles.

Charles responded: "You are all deadly rivals," to laughter.

Huang jokingly responded, "No one has to die," to which King Charles responded, "Really?" to more laughter.

Bezos recalled his efforts to raise $1 million from investors in 1995, when he could only raise $50,000 at a time and had 40 investors reject his request.

"Those 40 investors must be regretting it now," Charles responded, drawing laughter.

Charles compared those who gave up investing in Amazon to the many publishers who refused to publish the "Harry Potter" series of novels.

Charles's trip to the United States follows US President Trump's visit to the UK in September last year. During Trump's visit to the UK last year, US technology companies including Microsoft, Nvidia, Google and OpenAI pledged to invest 31 billion pounds ($42 billion) in the UK over the next few years in artificial intelligence, quantum computing and civilian nuclear energy.