BERLIN (AFP) - German regulators on Thursday (Nov 29) opened a probe into whether e-commerce giant Amazon was abusing its dominant position to obstruct competition from rival sellers on its online platform.

The Federal Cartel Office said it would look closely at Amazon's business practices after receiving "many complaints" from retailers and manufacturers selling goods through its German website amazon.de.

"Amazon functions as a kind of 'gatekeeper' for customers", Andreas Mundt, head of Germany's Federal Cartel Office, said in a statement.

"Its double role as the largest retailer and largest marketplace has the potential to hinder other sellers on its platform."

The probe is the latest setback for Amazon after the European Commission in September opened a preliminary investigation into suspicions the retailer uses the data it has about its third-party sellers to gain a competitive edge.

The Federal Cartel Office said its investigation would "supplement" the Brussels probe.

The German watchdog said it would examine Amazon's "terms of business and practices towards sellers", including taking a closer look at rules for product reviews, use of data and the "non-transparent" blocking or closing of sellers' accounts.

In a statement to AFP, Amazon said it could not comment on ongoing proceedings.

"But we will fully cooperate with the Federal Cartel Office and continue to work on supporting the growth of small and middle-sized companies," a spokesman said.

The company pointed out German SMEs had sold 2.1 billion euros (S$3.3 billion) in goods around the world through Amazon last year.

The probe comes as US tech giants Amazon, Facebook, Google and Apple are increasingly under scrutiny in Europe amid heightened concerns about data privacy and market dominance.