The founder and CEO of Facebook Mark Zuckerberg speaks during the 56th Munich Security Conference in Munich, southern Germany, on February 15, 2020.

EU industry commissioner Thierry Breton said on Monday it was for Facebook to adapt to Europe's standards, not the other way round, as he criticized the U.S. social media giant's proposed internet rules as insufficient.

The blunt comments came after a short meeting with Facebook CEO Mark Zuckerberg and two days before Breton is due to present the first of a raft of rules to rein in U.S. tech giants and state-aided Chinese companies.

"It's not for us to adapt to this company, it's for this company to adapt to us," Breton, a former CEO at French telecoms provider Orange and French technology company Atos, told reporters after the meeting.

Zuckerberg had earlier told reporters he had a good, wide-ranging conversation with Breton.

Breton also said he would decide by the end of the year whether to adopt tough rules as part of the digital services act to regulate online platforms and set out their responsibilities.

He dismissed a discussion paper issued by Facebook on Monday that rejects what it calls intrusive regulations and suggests looser rules whereby companies would periodicially report content and publish enforcement data.

"It's not enough," Breton said, adding that Facebook had omitted any mention of its market dominance and also failed to spell out its responsibilities.

EU justice chief Vera Jourova, who also met Zuckerberg, was equally adamant on Facebook's role in the fight against online hate speech, disinformation and election manipulation.

"Facebook cannot push away all the responsibility. Facebook and Mr Zuckerberg have to answer themselves a question 'who do they want to be' as a company and what values they want to promote," she said in a statement.

"It will not be up to governments or regulators to ensure that Facebook wants to be a force of good or bad."

Breton will announce proposals on Wednesday aimed at exploiting the EU's trove of industrial data and challenging the dominance of Facebook, Google and Amazon. It will announce rules to govern the use of artificial intelligence too, which will also affect companies such as Facebook.

Referring to the possibility that the EU may hold internet companies responsible for hate speech and other illegal speech published on their platforms, Facebook in its discussion document said this ignored the nature of the internet.

It urged regulators to understand the capabilities and limitations of technology in assessing content and allow internet companies the flexibility to innovate.

Zuckerberg's visit came on the heels of visits by Alphabet Chief Executive Sundar Pichai and Microsoft President Brad Smith to Brussels last month.