Google chief executive Sundar Pichai warned that Britain's decision to leave the European Union may bring difficulties for internet companies as digital regulation diverges.
"As companies we see great value in Europe as a unified digital market," Pichai told German newspaper Welt am Sonntag.
For a global company, it is a challenge to keep up with varying laws and regulations in every country, he said.
"The complexity makes a bigger commitment difficult, which can be seen in investments."
But large firms are still much better at dealing with different national regulations than smaller companies, he added.
"Smaller companies, which often drive innovation, can't afford that."
Pichai also used the opportunity to reject critique about the company's international tax practices, saying only politicians can advance the global tax system.
"If [new international tax] laws are passed, we would of course adhere to them."