The EC has proposed rules to combat “unfair trading practices” by leading online platforms and search engines including Google.

The commission said hotels and online traders would be among those to benefit from the rules aimed at creating “a fair, predictable, sustainable and trusted business environment” online.

The proposals provide for “increased transparency”, the introduction of dispute resolution schemes – including a right for business associations to bring court proceedings – and the establishment of an EU body to monitor the effectiveness of the measures.

“Providers of online intermediation” including Google, Facebook, Instagram and Skyscanner will be required to publish policies detailing:

“How they treat their own goods and services compared to those used by professional users; [and]

“How they use contract clauses to demand the most-favourable range or price of products and services.”

They will also be required to “set out the general criteria that determine how goods and services are ranked in search results”.

And they must give “reasonable minimum notice” of changes to terms and conditions.

Explaining the new rules, the Commission said: “The current position of online platforms as mediators of business customer relationships allows them to engage in unfair trading practices that can cause significant economic harm to the businesses that use them.”

A survey found almost half (46%) of business users have experienced difficulties, with heavy users “far more likely to experience problems”.

The proposals follow a two-year fact-finding exercise by the EC. They will reviewed within three years.

EC vice-president for the digital single market Andrus Ansip said: “Millions of mostly small traders in the EU depend on online platforms to reach their customers.

“We need a set of clear and basic rules to ensure a sustainable and predictable business environment.”

Elżbieta Bieńkowska, commissioner for the internal market, industry, entrepreneurship and SMEs, said: “We want to prevent the fragmentation of the Single Market through a patchwork of national rules.

“[This] approach will give EU businesses the transparency and redress mechanisms that will help them embrace the digital economy.”

Mariya Gabriel, commissioner for the digital economy and society, added: “Platforms and search engines are important channels for European businesses to reach consumers, but we must make sure they are not abusing their power.”

The European Technology and Travel Services Association (ETTSA) welcomed the EC’s “principles-based approach” to the proposals but said: “We are concerned by some elements.

“We hope that large traditional lobbies won’t use this proposal to try to implement protectionist and anti-competitive strategies.”