London is looking to tap the deep pockets of Silicon Valley

Mayor of London Sadiq Khan hopes to convince U.S. tech firms to invest more in London.

The mayor of London traveled to California to try to convince tech leaders to invest more money in the UK.

On Tuesday, Khan met with senior tech bosses including Ruth Porat, venture capital investors and entrepreneurs from the Bay Area.

London and Silicon Valley have a strong relationship.

He wants more U.S. tech firms to open in London. He wants more U.S. tech investors to back more London start-ups.

Silicon Valley venture capital powerhouses like Lightspeed and Sequoia have recently set up outposts in the city to help them find start-up investment opportunities, while U.S. tech giants like Apple and Amazon already have large offices in the capital.

Ahead of his meetings, Khan said in a statement that he planned to "bang the drum for even more investment in London by American tech companies."

There were fears that a mass exodus from the U.S. tech would happen after the UK leaves the EU.

Tens of thousands of people are employed by U.S. tech giants in London, with many of them in highly-paid roles that contribute to the city's overall economy.

The Central St. Giles building is in London's West End and is currently being paid $1 billion.

Apple is set to be one of the main tenants of the Battersea Power Station redevelopment, as well as being in the process of building a vast new office with enough space for over 4,000 staff on a site behind King's Cross train station.

Google’s new London headquarters.

Since we first opened our offices in London in 2003 we have invested in our local offices, employees and R&D.

The Mayor believes in the power of technology to drive sustainable economic growth, and we look forward to continuing to deepen our connection to the capital in the years ahead.

According to research published Wednesday, London is the number one destination for U.S. tech companies that are looking to expand internationally.

Tech companies can create jobs, but they can also push up house prices. In the last decade, property prices in King's Cross and Shoreditch have gone up as companies like Amazon have moved in.

In June 2010, the average house price in N1 was 561,671, according to property website Rightmove. A range of factors contributed to the surge, including government and central bank stimulation.